Damper device

ABSTRACT

A damper device includes a plurality of rotational elements, a plurality of elastic bodies, a rotary inertia mass damper and a housing that houses the plurality of rotational elements, the plurality of elastic bodies and the rotary inertia mass damper, the housing including a front cover. The rotary inertia mass damper is configured to include a planetary gear that includes a sun gear, a plurality of pinion gears, and a carrier that rotatably supports the plurality of pinion gears. The carrier is centered by either the sun gear or a member that rotates integrally with the sun gear by being radially supported by either the sun gear or the member that rotates integrally with the sun gear. In addition, the carrier is spline-engaged to the front cover when a lockup clutch is engaged.

This application is a divisional application of application Ser. No.16/062,823, filed Jun. 15, 2018, which is the National Stage ofInternational Application No. PCT/JP2017/003184 filed Jan. 30, 2017,which claims the benefit of Japanese Patent Application No.JP2016-016466 filed Jan. 29, 2016, the contents of which areincorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a damper device including a rotaryinertia mass damper.

BACKGROUND

A conventionally known torsional vibration damper includes a rotaryinertia mass damper with a planetary gear that includes a sun gear (87),a pinion gear (83) and a ring gear (106) (as shown in, for example,Patent Literature 1). The torsional vibration damper includes a coverplate (79) that is fixed to a turbine shell (29) and forms a drive sidedamper element (81) of the torsional vibration damper together withanother cover plates (97, 99) fixed thereto, and a spring (100) thattransmits a torque between the cover plates (79-99) and the sun gear(87). The sun gear (87) is disposed between the cover plates (79, 97) inan axial direction so as to work as a driven side damper element (88).The cover plate (79) includes a journal portion (82) extruded to alockup piston (63) that is coupled with the turbine shell (29) via atransmission element (77). The pinion gear (83) that meshes with the sungear (87) and the ring gear (106) is rotatably supported by the lockuppiston (63) and the cover plate (79) or a carrier via the journalportion (82). In the conventional torsional vibration damper, the spring(100) is deflected and the ring gear (106) or a mass body rotates inaccordance with a relative rotation between the cover plates (79-97) andthe sun gear (87) when a lockup clutch is engaged and the cover plates(79-97) rotates (are twisted) with respect to the sun gear (87). Thus,an inertia torque according to a difference in angular accelerationbetween the cover plates (79-97) and the sun gear (87) is applied fromthe ring gear (106) or the mass body to the sun gear (87) or the outputelement of the torsional vibration damper via the pinion gear (83),thereby improving the vibration damping performance of the torsionalvibration damper.

CITATION LIST Patent Literature

PTL1: Japanese Patent Application Laid Open No. 2000-154863

SUMMARY

In the conventional torsional vibration damper, it is preferable torestrict the relative rotation between the cover plates and the sun gearfrom the viewpoint of protecting the spring when a larger torque istransmitted to the cover plate (input element) so that an excessive loadincluding the inertia torque from the rotary inertia mass damper doesnot act on the spring. However, the Patent Literature 1 does notdisclose anything with respect to a restriction of the relative rotationbetween the cover plates and the sun gear. Hence, there remains problemsin durability of the above torsional vibration damper.

A subject matter of the disclosure is to improve durability of thedamper device with the rotary inertia mass damper.

The disclosure is directed to a damper device. The damper device isconfigured to include a first rotational element to which a torque froman engine is transmitted, a second rotational element, a thirdrotational element, a first elastic body arranged to transmit a torquebetween the first element and the second element, a second elastic bodyarranged to transmit a torque between the second element and the thirdelement, and a rotary inertia mass damper with a mass body rotating inaccordance with relative rotation between the first rotational elementand the third rotational element. The damper device includes a stopperconfigured to restrict the relative rotation between the firstrotational element and the third rotational element. The rotary inertiamass damper is configured to include a planetary gear that includes asun gear, a plurality of pinion gears that mesh with the sun gear, and aring gear that works as the mass body. The first rotational element isconfigured to include a first rotational support member and a secondrotational support member that are coupled with each other so as to beopposed to each other in an axial direction of the damper device. Thefirst and the second rotational support members rotatably support theplurality of pinion gears. The third rotational element is configured toinclude an outer teeth gear portion that meshes with the plurality ofpinion gears in an outer circumferential portion thereof. The thirdrotational element is disposed between the first and the secondrotational support members in the axial direction so as to work as thesun gear. The stopper is configured to include a contact portionarranged in the outer circumferential portion of the third rotationalelement so as to contact with a portion of the first rotational elementin accordance with the relative rotation between the first rotationalelement and the third rotational element.

The damper device is capable of restricting the relative rotationbetween the first rotational element and the third rotational element soas to prevent an excessive load including the inertia torque from therotary inertia mass damper from acting on the first and the secondsprings when a larger torque is transmitted between the first and thethird rotational elements, thereby satisfactorily protecting the firstand the second springs. Further, the contact portion of the stopper isarranged in the outer circumferential portion of the third rotationalelement (sun gear) so as to make a distance from the axial center of thedamper device to the contact portion closer to a distance from the axialcenter of the damper device to a support portion of the pinion gears inthe first rotational element. This decreases moment acting on the firstrotational element (the first and the second rotational support members)that supports the plurality of pinion gears and prevents deformation andso on of the first rotational element when the contact portion contactswith the first rotational element so as to restrict the relativerotation between the first rotational element and the third rotationalelement. Accordingly, the durability of the damper device with therotary inertia mass damper can be improved.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic configuration diagram illustrating a startingdevice including a damper device according to the disclosure;

FIG. 2 is a sectional view illustrating the starting device illustratedin FIG. 1;

FIG. 3 is a front view illustrating the damper device of the startingdevice illustrated in FIGS. 1 and 2;

FIG. 4 is an enlarged sectional view illustrating a rotary inertia massdamper of the damper device according to the disclosure;

FIG. 5 is a diagram illustrating a relationship of rotation speed of anengine to torque variation T_(Fluc) at an output element in the damperdevice according to the disclosure;

FIG. 6 is a sectional view illustrating a starting device including adamper device according to another embodiment of the disclosure;

FIG. 7 is a front view illustrating the damper device of the startingdevice illustrated in FIG. 6;

FIG. 8 is a schematic configuration diagram illustrating a startingdevice including a damper device according to yet another embodiment ofthe disclosure;

FIG. 9 is a sectional view illustrating the starting device illustratedin FIG. 8;

FIG. 10 is a front view illustrating the damper device of the startingdevice illustrated in FIGS. 8 and 9;

FIG. 11 is a front view illustrating the damper device of the startingdevice illustrated in FIGS. 8 and 9 seen from a turbine runner side;

FIG. 12 is a sectional view illustrating a starting device including adamper device according to another embodiment of the disclosure; and

FIG. 13 is a sectional view illustrating a starting device including adamper device according to yet another embodiment of the disclosure.

DESCRIPTION OF EMBODIMENTS

The following describes some embodiments of the disclosure withreference to drawings.

FIG. 1 is a schematic configuration diagram illustrating a startingdevice 1 including a damper device 10 according to the disclosure. FIG.2 is a sectional view illustrating the starting device 1. The startingdevice 1 illustrated in these drawings is mounted on a vehicle equippedwith an engine (internal combustion engine) EG as a driving source andmay include, in addition to the damper device 10, for example, a frontcover 3 serving as an input member coupled with a crankshaft of theengine EG and configured to receive a torque transmitted from the engineEG, a pump impeller (input-side fluid transmission element) 4 fixed tothe front cover 3 in order to form a housing with the pump impeller 4, aturbine runner (output-side fluid transmission element) 5 arranged to berotatable coaxially with the pump impeller 4, a damper hub 7 serving asan output member connected with the damper device 10 and fixed to aninput shaft IS of a transmission TM that is either an automatictransmission (AT) or a continuously variable transmission (CVT), and alockup clutch 8.

In the description below, a term “axial direction” basically means anextending direction of a central axis (axial center) of the startingdevice 1 or the damper device 10, unless otherwise specified. A term“radial direction” basically means a radial direction of the startingdevice 1, the damper device 10 or a rotational element of the damperdevice 10 and so on, i.e., an extending direction of a straight lineextended in a direction perpendicular to the central axis (radialdirection) from the central axis of the starting device 1 or the damperdevice 10, unless otherwise specified. Additionally, a term“circumferential direction” basically means a circumferential directionof the starting device 1, the damper device 10 or a rotational elementof the damper device 10 and so on, i.e., a direction along a rotationdirection of the rotational element, unless otherwise specified.

As shown in FIG. 2, the pump impeller 4 includes a pump shell 40 closelyfixed to the front cover 3 to define a fluid chamber 9 in whichhydraulic oil flows and a plurality of pump blades 41 provided on aninner surface of the pump shell 40. As shown in FIG. 2, the turbinerunner 5 includes a turbine shell 50 and a plurality of turbine blades51 provided on an inner surface of the turbine shell 50. An innercircumferential portion of the turbine shell 50 is fixed to a turbinehub 52 by means of a plurality of rivets. The turbine hub 52 isrotatably supported by the damper hub 7. The motion of the turbine hub52 (turbine runner 5) in the axial direction of the starting device 1 isrestricted by the damper hub 7 and a snap ring fitted to the damper hub7.

The pump impeller 4 and the turbine runner 5 are opposed to each other,and a stator 6 is disposed coaxially between the pump impeller 4 and theturbine runner 5 to straighten the flow of hydraulic oil (hydraulicfluid) from the turbine runner 5 to the pump impeller 4. The stator 6includes a plurality of stator blades 60. The rotation direction of thestator 6 is set to only one direction by a one-way clutch 61. The pumpimpeller 4, the turbine runner 5 and the stator 6 form a torus (annularflow path) to circulate the hydraulic oil and work as a torque converter(fluid transmission device) with the torque amplification function. Inthe starting device 1, however, the stator 6 and the one-way clutch 61may be omitted, and the pump impeller 4 and the turbine runner 5 maywork as fluid coupling.

The lockup clutch 8 is a hydraulic multi-plate clutch which executes andreleases a lockup in which the front cover 3 and the damper hub 7 arecoupled with each other via the damper device 10. The lockup clutch 8includes a lockup piston 80 slidably supported in the axial direction bya center piece 30 which is fixed to the front cover 3, a clutch drum 81,an annular clutch hub 82 fixed to an inner surface of a side wallportion 33 of the front cover 3 to oppose to the lockup piston 80, aplurality of first friction engagement plates (friction plates with afriction material on both surfaces) 83 engaged to splines formed on aninner circumference of the clutch drum 81, and a plurality of secondfriction engagement plates 84 (separator plates) engaged to splinesformed on an outer circumference of the clutch hub 82.

Further, the lockup clutch 8 includes an annular flange member (oilchamber defining member) 85 attached to the center piece 30 of the frontcover 3 to be disposed on the side opposite to the front cover 3 withrespect to the lockup piston 80, that is, disposed on the side of theturbine runner 5 and the damper device 10 with respect to the lockuppiston 80, and a plurality of return springs 86 disposed between thefront cover 3 and the lockup piston 80. As illustrated in the drawing,the lockup piston 80 and the flange member 85 define an engagement oilchamber 87. Hydraulic oil (engagement hydraulic pressure) is supplied tothe engagement oil chamber 87 from a hydraulic control device (notillustrated). Increasing the engagement hydraulic pressure for theengagement oil chamber 87 moves the lockup piston 80 in the axialdirection such that the first and the second friction engagement plates83 and 84 are pressed toward the front cover 3, which brings the lockupclutch 8 into engagement (complete engagement or slip engagement). Ahydraulic single-plate clutch that includes a lockup piston to which afriction material is affixed may be adopted as the lockup clutch 8.

As shown in FIGS. 1 and 2, the damper device 10 includes a drive member(first rotational element) 11 or an input element, an intermediatemember (second rotational element) 12 or an intermediate element and adriven member (third rotational element) 15 or an output element, asrotational elements that are housed by the housing defined by the frontcover 3 and the pump impeller 4. The damper device 10 also includes aplurality of (for example, three in this embodiment) first springs(first elastic bodies) SP1 arranged to transmit the toque between thedrive member 11 and the intermediate member 12, a plurality of (forexample, three in this embodiment) second springs (second elasticbodies) SP2 arranged to respectively work in series with thecorresponding first springs SP1 and to transmit the torque between theintermediate member 12 and the driven member 15, and a plurality of (forexample, three in this embodiment) inner springs SPi arranged totransmit the torque between the drive member 11 and the driven member15, as torque transmission elements (torque transmission elastic bodies)that are also housed by the housing defined by the front cover 3 and thepump impeller 4.

As shown in FIG. 1, the damper device 10 has a first torque transmissionpath TP1 and a second torque transmission path TP2 that are providedparallel to each other between the drive member 11 and the driven member15. The first torque transmission path TP1 is configured by theplurality of first springs SP1, the intermediate member 12 and theplurality of second springs SP2 so as to transmit the torque between thedrive member 11 and the driven member 15 via these elements. In thisembodiment, coil springs having an identical specification (springconstant) are employed for the first and the second springs SP1 and SP2of the first torque transmission path TP1.

The second torque transmission path TP2 is configured by the pluralityof inner springs SPi so as to transmit the torque between the drivemember 11 and the driven member 15 via the plurality of inner springsSPi that work parallel to one another. In this embodiment, the pluralityof inner springs SPi of the second torque transmission path TP2 arearranged to work in parallel to the first and the second springs SP1 andSP2 of the first torque transmission path TP1, after an input torqueinto the drive member 11 reaches a predetermined torque (first thresholdvalue) T1 and a torsion angle of the drive member 11 relative to thedriven member 15 becomes equal to or larger than a predetermined angleθref. The damper device 10 accordingly has two-step (two-stage) dampingcharacteristics. The torque T1 is set to be smaller than a torque T2(second threshold value) corresponding to a maximum torsion angle θ maxof the damper device 10.

In this embodiment, a linear coil spring made of a metal material thatis spirally wound to have an axial center extended linearly at no loadis employed for the first and the second springs SP1 and SP2 and theinner springs SPi. Compared with employing an arc coil spring, this moreappropriately expands and contracts the first and the second springs SP1and SP2 and the inner springs SPi along their axial centers and reducesa difference between a torque transmitted to the driven member 15 fromthe second springs SP2 and so on when a relative displacement betweenthe drive member 11 and the driven member 15 increases and a torquetransmitted to the driven member 15 from the second springs SP2 and soon when the relative displacement between the drive member 11 and thedriven member 15 decreases, that is a hysteresis. The arc coil springmay, however, be employed for at least any of the first and the secondsprings SP1 and SP2 and the inner springs SPi.

As shown in FIGS. 2 and 3, the drive member 11 of the damper device 10includes an annular first input plate member (first rotational supportmember) 111 that is coupled with the clutch drum 81 of the lockup clutch8 and is aligned by the damper hub 7, and an annular second input platemember (second rotational support member) 112 that is coupled with thefirst input plate member 111 by means of a plurality of rivets 113 orcoupling members so as to be opposed with the first input plate member111. Accordingly, the drive member 11, or the first and the second inputplate members 111 and 112 rotate integrally with the clutch drum 81.Further, the front cover 3 (engine EG) is coupled with the drive member11 of the damper device 10 by engagement of the lockup clutch 8.Therefore, when the lockup clutch 8 is engaged, the clutch drum 81coupled with the first input plate member 111 as a carrier is connectedto a plurality of the first friction engagement plates 83 via a spline.Additionally, when the lockup clutch 8 is engaged, a plurality of thefirst friction engagement plates 83 is connected to the front cover 3 bythe lockup piston 80. That is, the first input plate member 111 issplined-engaged to the front cover 3 when the lockup clutch 8 isengaged.

In this embodiment, as shown in FIG. 2, the second input plate member112 of the drive member 11 is connected with the turbine shell 50 of theturbine runner 5 via a turbine coupling member 55. The turbine couplingmember 55 is an annular member fixed to the turbine shell 50 by means ofwelding. A plurality of (for example, three in this embodiment)engagement protrusions 55 e are formed at intervals (at equal intervals)in the circumferential direction in the outer circumferential portion ofthe turbine coupling member 55 so as to respectively extend in the axialdirection. Each of the engagement protrusions 55 e is fitted into anyone of a plurality of engagement recesses formed at intervals in thecircumferential direction in the outer circumferential portion of thesecond input plate member 112. Thus, the drive member 11 and the turbinerunner 5 are coupled with each other to be integrally rotated. Fittingthe turbine runner 5 into the second input plate member 112 allows theentire device to be compact and the turbine runner 5 and the secondinput plate member 112 to be easily coupled with each other. The secondinput plate member 112 and the turbine runner 5 may be coupled with eachother by means of rivets, for example.

As shown in FIGS. 2 and 3, the first input plate member 111 isconfigured to include a plurality of (for example, three in thisembodiment) arc-shaped outer spring-accommodating windows 111 woarranged at intervals (at equal intervals) in the circumferentialdirection, a plurality of (for example, three in this embodiment)arc-shaped inner spring-accommodating windows 111 wi arranged on aninner side in the radial direction of each outer spring-accommodatingwindow 111 wo at intervals (at equal intervals) in the circumferentialdirection, a plurality of (for example, three in this embodiment) springsupport portions 111 s respectively extending along an outercircumferential edge of each inner spring-accommodating window 111 wi, aplurality of (for example, three in this embodiment) outer springcontact portions 111 co, and a plurality of (for example, six in thisembodiment) inner spring contact portions 111 ci. The innerspring-accommodating windows 111 wi respectively have a circumferentiallength longer than a natural length of the inner spring SPi (see FIG.3). One outer spring contact portion 111 co is disposed between theouter spring-accommodating windows 111 wo arranged adjacent to eachother in the circumferential direction. One inner spring contact portion111 ci is disposed on each side in the circumferential direction of eachinner spring-accommodating window 111 wi.

The second input plate member 112 is configured to include a pluralityof (for example, three in this embodiment) arc-shaped outerspring-accommodating windows 112 wo arranged at intervals (at equalintervals) in the circumferential direction, a plurality of (forexample, three in this embodiment) arc-shaped inner spring-accommodatingwindows 112 wi arranged on an inner side in the radial direction of eachouter spring-accommodating window 112 wo at intervals (at equalintervals) in the circumferential direction, a plurality of (forexample, three in this embodiment) spring support portions 112 srespectively extending along an outer circumferential edge of each innerspring-accommodating window 112 wi, a plurality of (for example, threein this embodiment) outer spring contact portions 112 co, and aplurality of (for example, six in this embodiment) inner spring contactportions 112 ci. The inner spring-accommodating windows 112 wirespectively have a circumferential length longer than the naturallength of the inner spring SPi (see FIG. 3). One outer spring contactportion 112 co is disposed between the outer spring-accommodatingwindows 112 wo arranged adjacent to each other in the circumferentialdirection. One inner spring contact portion 112 ci is disposed on eachside in the circumferential direction of each inner spring-accommodatingwindow 112 wi. In this embodiment, the first and the second input platemembers 111 and 112 have an identical shape so as to reduce the numberof kinds of parts.

The intermediate member 12 includes a first intermediate plate member(first rotational member) 121 that is disposed on the front cover 3-sideof the first input plate member 111 of the drive member 11, and a secondintermediate plate member 122 that is disposed on the turbine runner5-side of the second input plate member (second rotational member) 112of the drive member 11 and coupled with the first intermediate platemember 121 by means of a plurality of rivets. As shown in FIG. 2, thefirst and the second input plate members 111 and 112 are disposedbetween the first intermediate plate member 121 and the secondintermediate plate member 122 in the axial direction of the damperdevice 10. That is, the intermediate member 12 includes the annularfirst and second intermediate plate members 121 and 122 that arearranged on both sides of the drive member 11 and coupled with eachother. This configuration enhances the flexibility in design of a momentof inertia of the intermediate member 12 by an adjustment of inner andouter diameters and thickness of the first and second intermediate platemembers 121 and 122.

As shown in FIGS. 2 and 3, the first intermediate plate member 121 isconfigured to include a plurality of (for example, three in thisembodiment) arc-shaped spring-accommodating windows 121 w arranged atintervals (at equal intervals) in the circumferential direction, anannular spring support portion 121 s extending along outercircumferential edges of the plurality of spring-accommodating windows121 w, and a plurality of (for example, three in this embodiment) springcontact portions 121 c. One spring contact portion 121 c is disposedbetween the spring-accommodating windows 121 w arranged adjacent to eachother in the circumferential direction. In this embodiment, an innercircumferential surface of the first intermediate plate 121 is supportedfrom the inner side in the radial direction by the spring supportportion 111 s of the first input plate member 111 so that the firstintermediate plate member 121 is aligned by the first input plate member111. That is, the inner circumferential surface of the firstintermediate plate 121 is supported by the spring support portion 111 swhich is close to the axial center of damper device 10. Thisconfiguration enables the first intermediate plate 121 to be alignedwhile reducing a frictional force accompanied with the alignment of thefirst intermediate plate 121.

The second intermediate plate member 122 is configured to include aplurality of (for example, three in this embodiment) arc-shapedspring-accommodating windows 122 w arranged at intervals (at equalintervals) in the circumferential direction, an annular spring supportportion 122 s extending along outer circumferential edges of theplurality of spring-accommodating windows 122 w, and a plurality of (forexample, three in this embodiment) spring contact portions 122 c. Onespring contact portion 122 c is disposed between thespring-accommodating windows 122 w arranged adjacent to each other inthe circumferential direction. In this embodiment, an innercircumferential surface of the second intermediate plate 122 issupported from the inner side in the radial direction by the springsupport portion 112 s of the second input plate member 112 so that thesecond intermediate plate member 122 is aligned by the second inputplate member 112. That is, the inner circumferential surface of thesecond intermediate plate 122 is supported by the spring support portion112 s which is close to the axial center of damper device 10. Thisconfiguration enables the second intermediate plate 122 to be alignedwhile reducing a frictional force accompanied with the alignment of thesecond intermediate plate 122. In this embodiment, the first and thesecond intermediate plate members 121 and 122 have an identical shape soas to reduce the number of kinds of parts.

In this embodiment, the spring contact portions 121 c and 122 c of thefirst and the second intermediate plates 121 and 122 are opposed to eachother in the axial direction and coupled with each other by means ofrivets. Further, in this embodiment, the first intermediate plate 121includes a plurality of (for example, three in this embodiment) couplingflange portions 125 arranged at intervals (at equal intervals) in thecircumferential direction and located radially outside the springcontact portions 121 c, as shown in FIGS. 2 and 3. The secondintermediate plate 122 includes a plurality of (for example, three inthis embodiment) coupling flange portions 126 arranged at intervals (atequal intervals) in the circumferential direction and located radiallyoutside the spring contact portions 122 c, as shown in FIGS. 2 and 3.The spring contact portions 121 c and 122 c of the first and the secondintermediate plates 121 and 122 are opposed to each other in the axialdirection and coupled with each other by means of rivets. Each of thecoupling flange portions 125 of the first intermediate plate member 121opposes to the corresponding coupling flange portion 126 of the secondintermediate plate 122 in the axial direction. A pair of coupling flangeportions 125 and 126 is coupled with each other by means of a pluralityof (for example, two in this embodiment) rivets.

The driven member 15 is a plate-like annular member that is disposedbetween the first and the second input plate members 111 and 112 in theaxial direction and fixed to the damper hub 7 by means of a plurality ofrivets. As shown in FIGS. 2 and 3, the driven member 15 is configured toinclude a plurality of (for example, three in this embodiment)arc-shaped outer spring-accommodating windows 15 wo arranged atintervals (at equal intervals) in the circumferential direction, aplurality of (for example, three in this embodiment) arc-shaped innerspring-accommodating windows 15 wi arranged on an inner side in theradial direction of each outer spring-accommodating window 15 wo atintervals (at equal intervals) in the circumferential direction, aplurality of (for example, three in this embodiment) outer springcontact portions 15 co, and a plurality of (for example, six in thisembodiment) inner spring contact portions 15 ci. One outer springcontact portion 15 co is disposed between the outer spring-accommodatingwindows 15 wo arranged adjacent to each other in the circumferentialdirection. The inner spring-accommodating windows 15 wi respectivelyhave a circumferential length according to the natural length of theinner spring SPi. One inner spring contact portion 15 ci is disposed oneach side in the circumferential direction of each innerspring-accommodating window 15 wi.

One first spring SP1 and one second spring SP2 are disposed in the outerspring-accommodating windows 111 wo and 112 wo of the first and thesecond input plate members 111 and 112 and outer spring-accommodatingwindows 15 wo of the driven member 15, such that the first and thesecond springs SP1 and SP2 form a pair (to act in series). In themounting state of the damper device 10, the outer spring contactportions 111 co and 112 co of the first and the second input platemembers 111 and 112 and the outer spring contact portions 15 co of thedriven member 15 are respectively disposed between the first and thesecond springs SP1 and SP2 that are disposed in the different outerspring-accommodating windows 15 wo, 111 wo and 112 wo not to form a pair(not to act in series), and come into contact with ends of the first andthe second springs SP1 and SP2.

The spring contact portions 121 c and 122 c of the first and the secondintermediate plate members 121 and 122 are respectively disposed betweenthe common outer spring-accommodating windows 15 wo, 111 wo and 112 woto form a pair, and come into contact with ends of the first and thesecond springs SP1 and SP2. The first and the second springs SP1 and SP2disposed in the different outer spring-accommodating windows 15 wo, 111wo and 112 wo not to form a pair (not to act in series) are disposed inthe spring-accommodating windows 121 w and 122 w of the first and thesecond intermediate plate members 121 and 122. The first and the secondsprings SP1 and SP2 are supported (guided) from the outer side in theradial direction by the spring support portion 121 s of the firstintermediate plate member 121 on the front cover 3-side and the springsupport portion 122 s of the second intermediate plate member 122 on theturbine runner 5-side.

As shown in FIG. 3, the first and the second springs SP1 and SP2 arethus alternately arranged in the circumferential direction of the damperdevice 10. One end of each first spring SP1 comes into contact with thecorresponding outer spring contact portions 111 co and 112 co of thedrive member 11, and the other end of each first spring SP1 comes intocontact with the corresponding spring contact portions 121 c and 122 cof the intermediate member 12. One end of each second spring SP2 comesinto contact with the corresponding spring contact portions 121 c and122 c of the intermediate member 12, and the other end of each secondspring SP2 comes into contact with the corresponding outer springcontact portion 15 co of the driven member 15.

As a result, the first and the second springs SP1 and SP2 forming a pairare connected with each other in series via the spring contact portions121 c and 122 c of the intermediate member 12 between the drive member11 and the driven member 15. Accordingly, the damper device 10 furtherreduces the rigidity of the elastic bodies arranged to transmit thetorque between the drive member 11 and the driven member 15 or morespecifically a combined spring constant of the first and the secondsprings SP1 and SP2. In this embodiment, as shown in FIG. 3, theplurality of first springs SP1 and the plurality of second springs SP2are arranged on an identical circumference, such that the distancebetween the axial center of the starting device 1 or the damper device10 and the axial center of each first spring SP1 is equal to thedistance between the axial center of the starting device 1 and so on andthe axial center of each second spring SP2.

The inner spring SPi is disposed in each of the innerspring-accommodating windows 15 wi of the driven member 15. In themounting state of the damper device 10, each of the inner spring contactportions 15 ci comes into contact with a corresponding end of the innerspring SPi. In the mounting state of the damper device 10, a side of theeach inner spring SPi on the front cover 3-side is located in acircumferential center of the corresponding inner spring-accommodatingwindow 111 wi of the first input plate member 111 and supported (guided)from the outer side in the radial direction by the spring supportportion 111 s of the first input plate member 111. In the mounting stateof the damper device 10, a side of the each inner spring SPi on theturbine runner 5-side is located in a circumferential center of thecorresponding inner spring-accommodating window 112 wi of the secondinput plate member 112 and supported (guided) from the outer side in theradial direction by the spring support portion 112 s of the second inputplate member 112.

As shown in FIGS. 2 and 3, each of the inner springs SPi is arranged inan inner circumferential-side region in the fluid chamber 9 so as to besurrounded by the first and the second springs SP1 and SP2. Thisconfiguration further shortens the axial length of the damper device 10and thereby the axial length of the starting device 1 and reduces acentrifugal force applied to the inner springs SPi so as to decrease africtional force (sliding resistance) generated when each of the innersprings SPi are pressed against the spring supporting portions 111 s and112 s and the driven member 15 by the centrifugal force. Each of theinner springs SPi comes into contact with one pair of the inner springcontact portions 111 ci and 112 ci disposed on the respective sides ofthe inner spring-accommodating windows 111 wi and 112 wi of the firstand the second input plate members 111 and 112 when the input torque(drive torque) into the drive member 11 reaches the above torque T1.

Additionally, as shown in FIGS. 1 and 2, the damper device 10 includes arotary inertia mass damper 20 that is housed by the housing defined bythe front cover 3 and the pump impeller 4 and that is connected with thedrive member 11 (first rotational element) and the driven member 15(third rotational element) and is arranged parallel to both the firsttorque transmission path TP1 and the second torque transmission pathTP2. In this embodiment, the rotary inertia mass damper 20 is configuredto include a single pinion-type planetary gear 21 disposed between thedrive member 11 or the input element of the damper device 10 and thedriven member 15 or the output element of the damper device 10.

The planetary gear 21 is configured by the driven member 15 thatincludes a plurality of outer teeth gear portions 15 t in an outercircumference thereof so as to work as a sun gear, the first and thesecond input plate members 111 and 112 that rotatably support aplurality of (for example, three in this embodiment) pinion gears 23respectively engaging with the corresponding outer teeth gear portion 15t so as to work as a carrier, and a ring gear 25 that is disposedconcentrically with the driven member 15 (outer teeth gear portions 15t) or the sun gear and has inner teeth 25 t engaging with the eachpinion gear 23. Accordingly, in the fluid chamber 9, the driven member15 or the sun gear, the plurality of pinion gears 23 and the ring gear25 at least partially overlap with the first and the second springs SP1and SP2 (and inner springs SPi) in the axial direction as viewed in theradial direction of the damper device 10 (see FIG. 2).

As shown in FIG. 3, the outer teeth gear portions 15 t are formed on aplurality of predetermined portions of an outer circumferential surface(outer circumferential portion) of the driven member 15 at intervals (atequal intervals) in the circumferential direction. As seen from FIG. 2,the outer teeth gear portions 15 t are located radially outside theouter spring-accommodating window 15 wo and the innerspring-accommodating window 15 wi, that is, the first spring SP1, thesecond spring SP2 and the inner spring SPi that transmit the torquebetween the drive member 11 and the driven member 15. The outer teethgear portion 15 t may be formed on the entire outer circumferenceportion (outer circumferential surface) of the driven member 15.

As shown in FIGS. 2 and 3, the first input plate member 111 forming thecarrier of the planetary gear 21 is configured to include a plurality of(for example, three in this embodiment) pinion gear supporting portions115 disposed radially outside the outer spring contact portions 111 coat intervals (at equal intervals) in the circumferential direction.Similarly, the second input plate member 112 forming the carrier of theplanetary gear 21 is configured to include a plurality of (for example,three in this embodiment) pinion gear supporting portions 116 disposedradially outside the outer spring contact portions 112 co at intervals(at equal intervals) in the circumferential direction, as shown in FIGS.2 and 3.

As shown in FIG. 4, each of the pinion gear supporting portions 115 ofthe first input plate member 111 is configured to include an arc-shapedaxially extending portion 115 a configured to axially protrude towardthe front cover 3 and an arc-shaped flange portion 115 f radiallyextended outward from an end of the axially extending portion 115 a.Each of the pinion gear supporting portions 116 of the second inputplate member 112 is configured to include an arc-shaped axiallyextending portion 116 a configured to axially protrude toward theturbine runner 5 and an arc-shaped flange portion 116 f radiallyextended outward from an end of the axially extending portion 116 a.Each of the pinion gear supporting portions 115 (flange portion 115 f)of the first input plate member 111 is opposed to the correspondingpinion gear supporting portions 116 (flange portion 116 f) of the firstinput plate member 112 in the axial direction. The flange portions 115 fand 116 f forming a pair respectively support an end of a pinion shaft24 inserted into the pinion gear 23.

As shown in FIG. 3, a pair of flange portions 115 f and 116 f is coupledwith each other by means of a plurality of (for example, two in thisembodiment) rivets 113. The pinion shafts are arranged on an identicalcircumference (identical diameter) together with the two rivets 113.This configuration secures rigidity of the first and the second inputplate member 111 and 112 or the carrier. In this embodiment, the piniongear supporting portions 115 (flange portions 115 f) of the first inputplate member 111 are fixed to the clutch drum 81 of the lockup clutch 8by means of welding.

As shown in FIG. 4, the pinion gears 23 of the planetary gear 21 areconfigured to include an annular gear body 230 having gear teeth (outerteeth) 23 t in an outer circumference thereof, a plurality of needlebearings 231 disposed between an inner circumferential surface of thegear body 230 and an outer circumferential surface of the pinion shaft24, a pair of spacers 232 engaged to both ends of the gear body 230 soas to restricts an axial motion of the needle bearing 231. As shown inFIG. 4, the gear body 230 of the pinion gear 23 includes annularradially supporting portions 230 s that respectively protrude outside anaxial end of the gear teeth 23 t in an inner side of bottoms of the gearteeth 23 t in the radial direction of the pinion gear 23 and have acylindrical outer circumferential surface. A diameter of an outercircumferential surface of each spacer 232 is identical to or smallerdiameter than that of the radially supporting portion 230 s.

The plurality of pinion gears 23 (pinion shafts 24) are supported atintervals (at equal intervals) in the circumferential direction by thefirst and the second input plate members 111 and 112 (pinion gearsupporting portions 115 and 116) or the carrier. A washer 235 isdisposed between a side face of each spacer 235 and the pinion gearsupporting portion 115 or 116 (flange portion 115 f or 116 f) of thefirst or the second input plate member 111 or 112. As shown in FIG. 4,an axial gap is defined between both side faces of the gear teeth 23 tof the pinion gear 23 and the pinion gear supporting portion 115 or 116(flange portion 115 f or 116 f) of the first or the second input platemember 111 or 112.

The ring gear 25 of the planetary gear 21 is configured to include anannular gear body 250 having inner teeth 25 t in an inner circumferencethereof, two annular-shaped side plates 251, a plurality of rivets 252for fixing the each side plate 251 to both axial side face of the gearbody 250. The gear body 250, the two side plates 251 and the pluralityof rivets 252 are integrated each other and work as a mass body of therotary inertia mass damper 20. In this embodiment, the inner teeth 25 tis formed on the entire inner circumference of the gear body 250. Theinner teeth 25 t may be formed on a plurality of predetermined portionsof the inner circumferential surface of the gear body 250 at intervals(at equal intervals) in the circumferential direction. As shown in FIG.3, recessed portions may be formed on an outer circumferential surfaceof the gear body 250 so as to adjust a weight of the ring gear 25.

Each of the side plates 251 has a concave cylindrically shaped innercircumferential surface and works as a supported portion that is axiallysupported by the plurality of pinion gears 23 engaging with the innerteeth 25 t. That is, in both axial ends of the inner teeth 25 t, the twoside plates 251 are respectively fixed to the corresponding side face ofthe gear body 250 so as to protrude inside bottoms of the inner teeth 25t in the radial direction and oppose to at least the side face of thegear teeth 23 t of the pinion gear 23. As shown in FIG. 4, in thisembodiment, the inner circumferential surface of each side plate 251 islocated slightly inside tips of the inner teeth 25 t.

When each of the pinion gears 23 meshes with the inner teeth 25 t, theinner circumferential surface of each side plate 251 is supported by thecorresponding radially supporting portion 230 s of the pinion gear 23(gear body 230). This enables the ring gear 25 to be accurately alignedwith respect to the axial center of the driven member 15 or the sun gearby the radially supporting portions 230 s of the plurality of piniongears 23 and to smoothly rotate (oscillate). Further, when each of thepinion gears 23 meshes with the inner teeth 25 t, an inner face of eachside plate 251 opposes to the side face of the gear teeth 23 t of thepinion gear 23 and a side face of a portion from the bottoms of the gearteeth 23 t to the radially supporting portion 230 s. Accordingly, anaxial motion of the ring gear 25 is restricted by at least the side faceof the gear teeth 23 t of the pinion gear 23. Further, as shown in FIG.4, an axial gap is defined between an outer face of each side plate 251of the ring gear 25 and the pinion gear supporting portion 115 or 116(flange portion 115 f or 116 f) of the first or the second input platemember 111 or 112.

The damper device 10 further includes a stopper 17 configured torestrict a relative rotation between the drive member 11 and the drivenmember 15. In this embodiment, the stopper 17 includes a plurality of(for example, three in this embodiment) stopper contact portions 15 stformed at intervals in the circumferential direction in the outercircumferential surface portion of the driven member 15 so as to contactwith a portion of the drive member 11 in accordance with the relativerotation between the drive member 11 and the driven member 15. As seenfrom FIGS. 2 and 3, each of the stopper contact portions 15 st isextended in the axial direction from an outer circumferential portion ofthe driven member 15 so as to be located between the adjacent outerteeth gear portions 15 t in the circumferential direction and contactwith a root portion of the axially extending portion 115 a (see FIG. 4).In this embodiment, the outer circumferential portion of the drivenmember 15 may be bent toward the first input plate member 111 bypressing so as to form each of the stopper contact portions 15 st. Eachof the stopper contact portions 15 st may be a dowel formed in the outercircumferential portion of the driven member 15 by pressing.

In the mounting state of the damper device 10, each of the stoppercontact portions 15 st of the driven member 15 is disposed in thevicinity of a center between two adjacent pinion gear support portions115 (axially extending portions 115 a) of the first input plate member111 in the circumferential direction so as not to contact with the twoadjacent pinion gear support portions 115. Each of the stopper contactportions 15 st approaches the corresponding pinion gear support portion115 of the first input plate member 111 in accordance with the relativerotation between the drive member 11 and the driven member 15 and comesinto contact with the root portion of the corresponding axiallyextending portion 115 a when the input torque reaches the above torqueT2 corresponding to the maximum torsion angle θ max of the damper device10. Thus, the stopper 17 restricts the relative rotation between thedrive member 11 and the driven member 15 and the deflections of all ofthe springs SP1, SP2 and SPi.

When the lockup by the lockup clutch 8 is released in the startingdevice 1 with the configuration described above, as seen from FIG. 1,the torque (power) transmitted from the engine EG to the front cover 3is transmitted to the input shaft IS of the transmission TM via the pathof the pump impeller 4, the turbine runner 5, the drive member 11, thefirst springs SP1, the intermediate member 12, the second springs SP2,the driven member 15 and the damper hub 7. When the lockup is executedby the lockup clutch 8 of the starting device 1, on the other hand, thetorque transmitted from the engine EG to the drive member 11 via thefront cover 3 and the lockup clutch 8 is transmitted to the drivenmember 15 and the damper hub 7 via the first torque transmission pathTP1 including the plurality of first springs SP1, the intermediatemember 12 and the plurality of second springs SP2, and the rotaryinertia mass damper 20 until the input torque reaches the above torqueT1. When the input torque becomes equal to or higher than the abovetorque T1, the torque transmitted to the drive member 11 is transmittedto the driven member 15 and the damper hub 7 via the first torquetransmission path TP1, the second torque transmission path TP2 includingthe plurality of inner springs SPi, and the rotary inertia mass damper20 until the input torque reaches the above torque T2.

When the drive member 11 is rotated (twisted) relative to the drivenmember 15 under an execution of the lockup (engagement of the lockupclutch 8), the first and the second springs SP1 and SP2 are deflected,and the ring gear 25 or the mass body is rotated (oscillated) about theaxial center in accordance with relative rotation between the drivemember 11 and the driven member 15. More specifically, when the drivemember 11 is rotated (oscillated) relative to the driven member 15, therotation speed of the drive member 11 (first and the second input platemembers 111 and 112) or the carrier which is an input element of theplanetary gear 21 becomes higher than the rotation speed of the drivenmember 15 or the sun gear. In such a state, the rotation speed of thering gear 25 is increased by the action of the planetary gear 21, sothat the ring gear 25 is rotated at a higher rotation speed than therotation speed of the drive member 11. This causes an inertia torque tobe applied from the ring gear 25 that is the mass body of the rotaryinertia mass damper 20 to the driven member 15 that is the outputelement of the damper device 10 via the pinion gears 23 and therebydamps the vibration of the driven member 15. The rotary inertia massdamper 20 is configured to mainly transmit the inertia torque betweenthe drive member 11 and the driven member 15 but not to transmit anaverage torque.

When the input torque into the drive member 11 becomes equal to orhigher than the above torque T2, the stopper 17 restricts the relativerotation between the drive member 11 and the driven member 15 and thedeflections of all of the springs SP1, SP2 and SPi. This prevents anexcessive load including the inertia torque from the rotary inertia massdamper 20 from acting on the first and the second springs SP1, SP2 andthe inner springs SPi, thereby satisfactorily protecting these members.

The following describes a design procedure of the damper device 10.

As described above, in the damper device 10, until the input torquetransmitted to the drive member 11 reaches the above torque T1, thefirst and the second springs SP1 and SP2 included in the first torquetransmission path TP1 work in parallel to the rotary inertia mass damper20. When the first and the second springs SP1 and SP2 work in parallelto the rotary inertia mass damper 20, the torque transmitted from thefirst torque transmission path TP1 including the intermediate member 12and the first and the second springs SP1 and SP2 to the driven member 15depends on (is proportional to) the displacement (amount of deflectionor torsion angle) of the second springs SP2 between the intermediatemember 12 and the driven member 15. The torque transmitted from therotary inertia mass damper 20 to the driven member 15, on the otherhand, depends on (is proportional to) a difference in angularacceleration between the drive member 11 and the driven member 15, i.e.,a second order differential equation result of the displacement of thefirst and the second springs SP1 and SP2 between the drive member 11 andthe driven member 15. On the assumption that the input torquetransmitted to the drive member 11 of the damper device 10 isperiodically vibrated as shown by Equation (1) given below, the phase ofthe vibration transmitted from the drive member 11 to the driven member15 via the first torque transmission path TP1 is accordingly shifted by180 degrees from the phase of the vibration transmitted from the drivemember 11 to the driven member 15 via the rotary inertia mass damper 20.[Math. 1]T=T ₀ sin ωt  (1)

Additionally, in the damper device 10 including the intermediate member12, two resonances can be set in a state where the deflections of thefirst and the second springs SP1 and SP2 are allowed and the innersprings SPi are not deflected. That is, on the assumption that a torquetransmission from the engine EG to the drive member 11 starts in a statewhere the lockup is executed by the lockup clutch 8 of the startingdevice 1, a resonance caused by the vibrations of the drive member 11and the driven member 15 in the opposite phases or a resonance (firstresonance, see a resonance point R1 in FIG. 5) of mainly thetransmission TM between the drive member 11 and drive shafts (not shown)occurs in the first torque transmission path TP1 when the deflections ofthe first and the second springs SP1, SP2 are allowed and the innersprings SPi are not deflected.

Further, the intermediate member 12 of the first torque transmissionpath TP1 is formed in an annular shape. This causes the inertia forceapplied to the intermediate member 12 to be greater than the resistanceforce of interfering with vibration of the intermediate member 12(frictional force caused by the centrifugal force mainly applied to therotating intermediate member 12) in the process of transmitting thetorque from the engine EG to the drive member 11. Accordingly, a dampingratio ζ of the intermediate member 12 that is vibrated with transmissionof the torque from the engine EG to the drive member 11 becomes lessthan a value 1. The damping ratio ζ of the intermediate member 12 in asingle-degree-of-freedom system may be expressed asζ=C/(2·√(J₂·(k₁+k₂)). Herein “J₂” denotes a moment of inertia of theintermediate member 12 (total moment of inertia of the intermediatemember 12 and the turbine runner 5 according to this embodiment), “k₁”denotes a combined spring constant of the plurality of first springs SP1working in parallel between the drive member 11 and the intermediatemember 12, “k₂” denotes a combined spring constant of the plurality ofsecond springs SP2 working in parallel between the intermediate member12 and the driven member 15, and “C” denotes a damping force (resistancefore) per unit speed of the intermediate member 12 that interferes withthe vibration of the intermediate member 12. Accordingly the dampingratio ζ of the intermediate member 12 is determined based on at leastthe moment of inertia J₂ of the intermediate member 12 and therigidities k₁ and k₂ of the first and the second springs SP1 and SP2.

The above damping force C may be determined by a procedure given below.When a displacement x of the intermediate member 12 is expressed asx=A·sin (ω₁₂·t), a loss energy Sc by the above damping force C may beexpressed as Sc=π·C·A²·ω₁₂ (where “A” denotes an amplitude and “ω₁₂”denotes a vibration frequency of the intermediate member 12).Additionally, when the displacement x of the intermediate member 12 isexpressed as x=A·sin(ω₁₂·t), a loss energy Sh by the above hysteresis Hin one cycle vibration of the intermediate member 12 may be expressed asSh=2·H·A. On the assumption that the loss energy Sc by the above dampingforce C is equal to the loss energy Sh by the hysteresis H, the abovedamping force C may be expressed as C=(2·H)/(π·A·ω₁₂).

Additionally, a natural frequency f₁₂ of the intermediate member 12 inthe single-degree-of-freedom system is expressed asf₁₂=½π·√((k₁+k₂)/J₂). Forming the intermediate member 12 in an annularshape relatively increases the moment of inertia J₂, so that the naturalfrequency f₁₂ of the intermediate member 12 relatively decreases.Accordingly, as shown in FIG. 5, in the state that the deflections ofthe first and the second springs SP1 and SP2 are allowed and the outersprings SPo are not deflected, the resonance of the intermediate member12 (second resonance, see a resonance point R2 in FIG. 5) by thevibration of the intermediate member 12 in the opposite phase to thoseof the drive member 11 and the driven member 15 occurs in the firsttorque transmission path TP1 at the stage when the rotation speed of thedrive member 11 reaches a rotation speed corresponding to the greaterbetween the two natural frequencies, i.e., at a higher rotation speed(higher frequency) than the first resonance.

In order to further improve the vibration damping effect of the damperdevice 10 with the above characteristics, as the result of intensivestudies and analyses, the inventors have noted that the damper device 10can damp the vibration of the driven member 15 by making the amplitudeof the vibration of the first torque transmission path TP1 equal to theamplitude of the vibration of the rotary inertia mass damper 20 in theopposite phase. The inventors have established an equation of motion asshown by Equation (2) given below in a vibration system including thedamper device 10 in which the torque is transmitted from the engine EGto the drive member 11 under engagement of the lockup clutch and theinner springs SPi are not deflected. In Equation (2), “J₁” denotes amoment of inertia of the drive member 11, “J₂” denotes a moment ofinertia of the intermediate member 12 as described above, “J₃” denotes amoment of inertia of the driven member 15, and “J₁” denotes a moment ofinertia of the ring gear 25 that is the mass body of the rotary inertiamass damper 20. Further, “θ₁” denotes a torsion angle of the drivemember 11, “θ₂” denotes a torsion angle of the intermediate member 12,“θ₃” denotes a torsion angle of the driven member 15. “λ” denotes a gearratio of the planetary gear 21 (a pitch circle diameter of the outerteeth gear portion 15 t (sun gear)/a pitch circle diameter of the innerteeth 25 t of the ring gear 25) included in the rotary inertia massdamper 20, that is, a ratio of a rotational speed of the ring gear 25 orthe mass body with respect to a rotational speed of the driven member15.

$\begin{matrix}{\mspace{79mu}\left\lbrack {{Math}.\mspace{14mu} 2} \right\rbrack} & \; \\{{\begin{bmatrix}{J_{1} + {J_{i} \cdot \left( {1 + \lambda} \right)^{2}}} & 0 & {{- J_{i}} \cdot \lambda \cdot \left( {1 + \lambda} \right)} \\0 & J_{2} & 0 \\{{- J_{i}} \cdot \lambda \cdot \left( {1 + \lambda} \right)} & 0 & {J_{3} + {J_{i} \cdot \lambda^{2}}}\end{bmatrix}\begin{bmatrix}{\overset{¨}{\theta}}_{1} \\{\overset{¨}{\theta}}_{2} \\{\overset{¨}{\theta}}_{3}\end{bmatrix}} + {\quad{{\begin{bmatrix}k_{1} & {- k_{1}} & 0 \\{- k_{1}} & {k_{1} + k_{2}} & {- k_{2}} \\0 & {- k_{2}} & k_{2}\end{bmatrix}\begin{bmatrix}\theta_{1} \\\theta_{2} \\\theta_{3}\end{bmatrix}} = \begin{bmatrix}T \\0 \\0\end{bmatrix}}}} & (2)\end{matrix}$

Additionally, the inventors have assumed that the input torque T isperiodically vibrated as shown by Equation (1) given above and have alsoassumed that the torsion angle θ₁ of the drive member 11, the torsionangle θ₂ of the intermediate member and the torsion angle θ₃ of thedriven member 15 are periodically responded (vibrated) as shown byEquation (3) given below. In Equations (1) and (3), “ω” denotes anangular frequency in the periodical fluctuation (vibration) of the inputtorque T. In Equation (3), “Θ₁” denotes an amplitude of the vibration(vibration amplitude, i.e., maximum torsion angle) of the drive member11 generated during transmission of the torque from the engine EG, “Θ₂”denotes an amplitude of vibration (vibration amplitude) of theintermediate member 12 generated during transmission of the torque fromthe engine EG to the drive member 11, and “Θ₃” denotes an amplitude ofvibration (vibration amplitude) of the driven member 15 generated duringtransmission of the torque from the engine EG to the drive member 11. Onsuch assumptions, an identity of Equation (4) given below is obtained bysubstituting Equations (1) and (3) into Equation (2) and eliminating“sin ωt” from both sides.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 3} \right\rbrack & \; \\{\begin{bmatrix}\theta_{1} \\\theta_{2} \\\theta_{3}\end{bmatrix} = {\begin{bmatrix}\Theta_{1} \\\Theta_{2} \\\Theta_{3}\end{bmatrix}\sin\;\omega\; t}} & (3) \\{\begin{bmatrix}T_{1} \\0 \\0\end{bmatrix} = {\begin{bmatrix}{k_{1} - {\omega^{2}\left\{ {J_{1} + {J_{i} \cdot \left( {1 + \lambda} \right)^{2}}} \right\}}} & {- k_{1}} & {\omega^{2} \cdot J_{i} \cdot \lambda \cdot \left( {1 + \lambda} \right)} \\{- k_{1}} & {k_{1} + k_{2} - {\omega^{2} \cdot J_{2}}} & {- k_{2}} \\{\omega^{2} \cdot J_{i} \cdot \lambda \cdot \left( {1 + \lambda} \right)} & {- k_{2}} & {k_{2} - {\omega^{2}\left( {J_{3} + {J_{i} \cdot \lambda^{2}}} \right)}}\end{bmatrix}\begin{bmatrix}\Theta_{1} \\\Theta_{2} \\\Theta_{3}\end{bmatrix}}} & (4)\end{matrix}$

In Equation (4), when the vibration amplitude θ₃ of the driven member 15is zero, this means that the vibration from the engine EG istheoretically damped completely by the damper device 10 and that novibration is theoretically transmitted to the transmission TM, thedriveshaft and so on located downstream of the driven member 15. Fromthis point of view, the inventors have obtained a conditional expressionof Equation (5) by solving the identity of Equation (4) with respect tothe vibration amplitude Θ₃ and setting Θ₃=0. Equation (5) is a quadraticequation with regard to the square of angular frequency ω² in theperiodical fluctuation of the input torque T. When the square of angularfrequency ω² is either of two real roots (or multiple root) of Equation(5), the vibration from the engine EG transmitted from the drive member11 to the driven member 15 via the first torque transmission path TP1and the vibration transmitted from the drive member 11 to the drivenmember 15 via the rotary inertia mass damper 20 are cancelled out eachother, and the vibration amplitude Θ₃ of the driven member 15theoretically becomes equal to zero.[Math. 4]J ₂ ·J _(i)·λ(1+λ)·(ω²)² −J _(i)·λ(1+λ)·(k ₁ +k ₂)·ω² +k ₁ ·k ₂=0  (5)

This result of analysis indicates that a total of two antiresonancepoints (A1 and A2 in FIG. 5) providing theoretically zero vibrationamplitude Θ₃ of the driven member 15 may be set in the damper device 10that includes the intermediate member 12 and accordingly provides twopeaks, i.e., a resonance in the torque transmitted via the first torquetransmission path TP1 as shown in FIG. 5. The damper device 10 can thussignificantly effectively damp the vibration of the driven member 15 bymaking the amplitude of the vibration of the first torque transmissionpath TP1 equal to the amplitude of the vibration of the rotary inertiamass damper 20 in the opposite phase at two points corresponding to thetwo resonances occurring in the first torque transmission path TP1.

Additionally, in the damper device 10, the resonance of the intermediatemember 12 occurs in the stage where the rotation speed of the drivemember 11 becomes rather higher than a rotation speed corresponding tothe frequency at an antiresonance point A1 of a lower rotation speedside (lower frequency side). The amplitude of the vibration transmittedfrom the second springs SP2 to the driven member 15 changes fromdecreasing to increasing before the rotation speed of the drive member11 (engine EG) reaches a rotation speed corresponding to the relativelylow natural frequency of the intermediate member 12, as shown by aone-dot chain line curve in FIG. 5. Even when the amplitude of thevibration transmitted from the rotary inertia mass damper 20 to thedriven member 15 is gradually increased with an increase in rotationspeed of the drive member 11 (as shown by a two-dot chain line curve inFIG. 5), this expands an area where the vibration transmitted from therotary inertia mass damper 20 to the driven member 15 cancels out atleast part of the vibration transmitted from the second springs SP2 tothe driven member 15. This results in further improving the vibrationdamping performance of the damper device 10 in a relatively low rotationspeed range of the drive member 11.

A vehicle equipped with the engine EG as the source of generating powerfor driving may be configured as to further decrease a lockup rotationspeed Nlup of the lockup clutch 8 (rotation speed at the time of firstcoupling of the engine EG with the damper device 10 after a start of theengine EG and the lowest among a plurality of lockup rotation speeds; inother words, minimum rotation speed in a rotation speed range where thetorque is transmitted from the drive member 11 through the torquetransmission path TP1 to the driven member 15) and mechanically transmitthe torque from the engine EG to the transmission TM at an earliertiming, so as to improve the power transmission efficiency between theengine EG and the transmission TM and thereby further improve the fuelconsumption of the engine EG. The vibration transmitted from the engineEG via the lockup clutch 8 to the drive member 11, however, increases ina low rotation speed range of approximately 500 rpm to 1500 rpm that islikely to be set as a range of the lockup rotation speed Nlup. Thevibration level significantly increases especially in a vehicle equippedwith a smaller-number cylinder engine such as three-cylinder engine orfour-cylinder engine. Accordingly, in order to suppress transmission ofa large vibration to the transmission TM and so on during or immediatelyafter engagement the lockup, there is a need to further reduce thevibration level in a rotation speed range of about the lockup rotationspeed Nlup of the entire damper device 10 (driven member 15) arranged totransmit the torque (vibration) from the engine EG to the transmissionTM under engagement of the lockup.

By taking into account the foregoing, the inventors have configured thedamper device 10 so as to form the antiresonance point A1 of the lowerrotation speed side (lower frequency side) when the rotation speed Ne ofthe engine EG is in the range of 500 rpm to 1500 rpm (in the expectedsetting range of the lockup rotation speed Nlup), based on thepredetermined lockup rotation speed Nlup of the lockup clutch 8. Twosolutions ω₁ and ω₂ of Equation (5) given above may be obtained asEquations (6) and (7) given below according to the quadratic formula,and satisfy ω₁<ω₂. A frequency fa₁ at the antiresonance point A1 of thelower rotation speed side (lower frequency side) (hereinafter referredto as “minimum frequency”) is expressed by Equation (8) given below, anda frequency fa₂ at an antiresonance point A2 of the higher rotationspeed side (higher frequency side) (fa₂>fa₁) is expressed by Equation(9) given below. A rotation speed Nea₁ of the engine EG corresponding tothe minimum frequency fa₁ is expressed as Nea₁=(120/n)·fa₁, where “n”denotes the number of cylinders of the engine EG.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 5} \right\rbrack & \; \\{\omega_{1}^{2} = \frac{\left( {k_{1} + k_{2}} \right) - \sqrt{\left( {k_{1} + k_{2}} \right)^{2} - {4 \cdot \frac{J_{2}}{J_{i}} \cdot k_{1} \cdot k_{2} \cdot \frac{1}{\lambda\left( {1 + \lambda} \right)}}}}{2 \cdot J_{2}}} & (6) \\{\omega_{2}^{2} = \frac{\left( {k_{1} + k_{2}} \right) + \sqrt{\left( {k_{1} + k_{2}} \right)^{2} - {4 \cdot \frac{J_{2}}{J_{i}} \cdot k_{1} \cdot k_{2} \cdot \frac{1}{\lambda\left( {1 + \lambda} \right)}}}}{2 \cdot J_{2}}} & (7) \\{{fa}_{1} = {\frac{1}{2\pi}\sqrt{\frac{\left( {k_{1} + k_{2}} \right) - \sqrt{\left( {k_{1} + k_{2}} \right)^{2} - {4 \cdot \frac{J_{2}}{J_{i}} \cdot k_{1} \cdot k_{2} \cdot \frac{1}{\lambda\left( {1 + \lambda} \right)}}}}{2 \cdot J_{2}}}}} & (8) \\{{fa}_{2} = {\frac{1}{2\pi}\sqrt{\frac{\left( {k_{1} + k_{2}} \right) + \sqrt{\left( {k_{1} + k_{2}} \right)^{2} - {4 \cdot \frac{J_{2}}{J_{i}} \cdot k_{1} \cdot k_{2} \cdot \frac{1}{\lambda\left( {1 + \lambda} \right)}}}}{2 \cdot J_{2}}}}} & (9)\end{matrix}$

Accordingly, the combined spring constant k₁ of the plurality of firstsprings SP1, the combined spring constant k₂ of the plurality of secondsprings SP2, the moment of inertia J₂ of the intermediate member 12, andthe moment of inertia J_(i) of the ring gear 25 that is the mass body ofthe rotary inertia mass damper 20 are selected and set in the damperdevice 10, in order to satisfy Expression (10) given below. Morespecifically, in the damper device 10, the spring constants k₁ and k₂ ofthe first and the second springs SP1 and SP2, the moment of inertia J₂of the intermediate member 12, the moment of inertia J_(i) of the ringgear 25, and the gear ratio λ of the planetary gear 21 are determined,based on the above minimum frequency fa₁ (and the lockup rotation speedNlup). When designing the damper device 10, a moment of the inertia ofthe pinion gear 23 may be ignored in practice as shown in Equations(2)-(9) and may be taken into account in the above equation (2) and soon. Further, the spring constants k₁ and k₂ of the first and the secondsprings SP1 and SP2, the moment of inertia J₂ of the intermediate member12, the moment of inertia J_(i) of the ring gear 25, the gear ratio λ ofthe planetary gear 21, and the moment of the inertia of the pinion gear23 may be determined, based on the above minimum frequency fa₁ (and thelockup rotation speed Nlup).

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 6} \right\rbrack & \; \\{{500\mspace{11mu}{rpm}} \leq {\frac{120}{n}{fa}_{1}} \leq {1500\mspace{11mu}{rpm}}} & (10)\end{matrix}$

As described above, the antiresonance point A1 of the lower rotationspeed side that is likely to provide theoretically zero vibrationamplitude Θ₃ of the driven member 15 (that is likely to further decreasethe vibration amplitude Θ₃) may be set in the low rotation speed rangeof 500 rpm to 1500 rpm (in the expected setting range of the lockuprotation speed Nlup). This enables one resonance having the lowerfrequency (first resonance) out of the resonances occurring in the firsttorque transmission path TP1 to be shifted toward the lower rotationspeed (toward the lower frequency) as shown in FIG. 5, so as to beincluded in a non-lockup area of the lockup clutch 8 (shown by thetwo-dot chain line curve in FIG. 5). Thus, the lockup (coupling of theengine EG with the drive member 11) at the lower rotation speed.

When the damper device 10 is configured to satisfy Expression (10), itis preferable to select and set the spring constants k₁ and k₂ and themoments of inertia J₂ and J_(i), so as to minimize the frequency of thelower rotation-speed (lower-frequency) side resonance (at a resonancepoint R1) occurring in the first torque transmission path TP1 to theminimum possible value that is lower than the above minimum frequencyfa₁. This further reduces the minimum frequency fa₁ and allows for thelockup at the further lower rotation speed.

Moreover, the configuration capable of setting two antiresonance pointsA1 and A2 enables the antiresonance point A1 having the minimumfrequency (fa₁) between the two antiresonance points A1 and A2 to beshifted toward the lower frequency side, compared with the configurationthat only one antiresonance point is set (shown by a broken line curvein FIG. 5). Additionally, as seen from FIG. 5, the configuration thatthe two antiresonance points A1 and A2 are set enables the vibrationfrom the engine EG transmitted from the drive member 11 to the drivenmember 15 via the first torque transmission path TP1 (shown by theone-dot chain line curve in FIG. 5) to be effectively damped by thevibration transmitted from the drive member 11 to the driven member 15via the rotary inertia mass damper 20 (shown by the two-dot chain linecurve in FIG. 5) in a relatively wide rotation speed range between thetwo antiresonance points A1 and A2.

This further improves the vibration damping effect of the damper device10 in the lower rotation speed range of a lockup area that is likely toincrease the vibration from the engine EG. In the damper device 10, onthe occurrence of the second resonance (resonance as shown by theresonance point R2 in FIG. 5), the intermediate member 12 is vibrated inthe opposite phase to that of the driven member 15. As shown by theone-dot chain line curve in FIG. 5, the phase of the vibrationtransmitted from the drive member 11 to the driven member 15 via thefirst torque transmission path TP1 becomes identical with the phase ofthe vibration transmitted from the drive member 11 to the driven member15 via the rotary inertia mass damper 20.

In the damper device 10 configured as described above, in order tofurther improve the vibration damping performance around the lockuprotation speed Nlup, there is a need to appropriately separate thelockup rotation speed Nlup and the rotation speed Ne of the engine EGcorresponding to the resonance point R2. Accordingly, when the damperdevice 10 is configured to satisfy Expression (10), it is preferable toselect and set the spring constants k₁ and k₂ and the moments of inertiaJ₂ and J_(i), so as to satisfy Nlup≤(120/n)·fa₁ (=Nea₁). This engagesthe lockup by the lockup clutch 8, while effectively suppressingtransmission of the vibration to the input shaft IS of the transmissionTM. This also enables the vibration from the engine EG to be remarkablyeffectively damped by the damper device 10, immediately after engagementof the lockup.

As described above, designing the damper device 10 based on thefrequency (minimum frequency) fa₁ at the antiresonance point A1remarkably effectively improves the vibration damping performance of thedamper device 10. According to the inventors' studies and analyses, ithas been confirmed that when the lockup rotation speed Nlup is set to,for example, a value of about 1000 rpm, the damper device 10 configuredto satisfy, for example, 900 rpm≤(120/n)·f_(a1)≤1200 rpm provides theremarkably effective results in practice.

Further, the drive member 11 of the damper device 10 includes the firstand the second input plate members 111 and 112 or the carrier, that arecoupled with each other so as to be opposed to each other in the axialdirection of the damper device 10 and rotatably support the plurality ofpinion gears 23 of the planetary gear 21. The driven member 15 includesthe plurality of outer teeth gear portions 15 t that respectively meshwith the corresponding pinion gear 23 in the outer circumferentialportion (outer circumferential surface) thereof and is disposed betweenthe first and the second input plate members 111 and 112 in the axialdirection so as to work as the sun gear. Further, the damper device 10includes the stopper 17 configured to restrict the relative rotationbetween the drive member 11 and the driven member 15. The stopper 17includes the stopper contact portions 15 st arranged in the outercircumferential portion of the driven member 15 so as to contact withthe portion of the drive member 11 or the first input plate member 111in accordance with the relative rotation between the drive member 111and the driven member 15.

Thus, the relative rotation between the drive member 11 and the drivenmember 15 is restricted so as to prevent the excessive load includingthe inertia torque from the rotary inertia mass damper 20 from acting onthe first and the second springs SP1 and SP2 and the inner springs SPiwhen a larger torque is transmitted between the drive member 11 and thedriven member 15, thereby satisfactorily protecting these members.Further, the stopper contact portions 15 st are arranged in the outercircumferential portion of the driven member 15 or the sun gear so as tomake a distance from the axial center of the damper device 10 to thestopper contact portion 15 st closer to a distance from the axial centerof the damper device 10 to a support portion of the pinion gear 23 or anaxial center of the pinion shaft 24 in the first and the second inputplate members 111 and 112. This decreases moment acting on the drivemember 11 that supports the plurality of pinion gears 23 and preventsdeformation and so on of the drive member 11 when the stopper contactportions 15 st contact with the first input plate member 111 so as torestrict the relative rotation between the drive member 11 and thedriven member 15. Accordingly, the durability of the damper device 10with the rotary inertia mass damper 20 can be improved.

The driven member 15 includes the plurality of outer teeth gear portions15 t arranged at intervals in the circumferential direction in the outercircumferential portion (outer circumferential surface) thereof. Theplurality of contact portions 15 st are arranged in the outercircumferential portion of the driven member 15 so as to be locatedbetween the adjacent outer teeth gear portions 15 t in thecircumferential direction. That is, in the driven member 15 or the sungear of the planetary gear 21 included in the rotary inertia mass damper20, each of the outer teeth gear portions 15 t may be formed in a rangecorresponding to a moving range of each pinion gear 23 and is notnecessarily required to be formed in the entire outer circumferentialportion of the driven member 15. Accordingly, when the plurality ofouter teeth gear portions 15 t are arranged at intervals in thecircumferential direction in the outer circumferential portion of thedriven member 15, the stopper contact portions 15 st may be respectivelylocated between the adjacent outer teeth gear portions 15 t in thecircumferential direction so as to suppress overall size expansion andcomplication of a structure of the drive member 11, the driven member 15and the damper device 10 even if the stopper contact portions 15 st arearranged in the driven member 15.

The stopper contact portions 15 st are respectively configured to extendin the axial direction from the outer circumferential portion of thedriven member 15 so as to be capable of contacting with one of the firstand the second input plate members 111 and 112 or the vicinity of theaxially extending portion 115 a of the first input plate member 111.This satisfactorily suppresses overall size expansion and complicationof the structure of the drive element 11, the driven member 15 and thedamper device 10 even if the stopper contact portions 15 st are arrangedin the driven member 15. The stopper contact portions 15 st may berespectively configured to extend in the axial direction from the outercircumferential portion of the driven member 15 so as to be capable ofcontacting with the second input plate member 112 (the vicinity of theaxially extending portion 116 a).

Further, as in a damper device 10X of a starting device 1X shown in FIG.6, the plurality of stopper contact portions 15 st are respectivelyconfigured to extend in the radial direction of the damper device 10 xfrom the outer circumferential portion of the driven member 15X so as tobe capable of contacting with the rivet 113 (coupling member) by whichthe first and the second input plate members 111 and 112 are coupled. Inthe damper device 10X, as shown in FIG. 7, each of the stopper contactportions 15 st is formed between the adjacent outer teeth gear portions15 t in the circumferential direction so as to radially protrude outsidethe outer teeth gear portions 15 t from the outer circumferentialportion of the driven member 15X. This enables the driven member 15X tobe formed flat, thereby reducing machining costs of the driven member15X.

In the damper device 10, 10X, the driven member 15, 15X or the sun gear,the plurality of pinion gears 23 and the ring gear 25 are arranged to atleast partially overlap with the first and the second springs SP1 andSP2 (and the inner spring SPi) in the axial direction of the damperdevice 10, 10X as viewed in the radial direction (see FIGS. 2, 3 and 6).This configuration further shortens the axial length of the damperdevice 10, 10X and further increases the moment of inertia of the ringgear 25 by disposing the ring gear 25 in the outer circumference side ofthe damper device 10 while suppressing an increase of the weight of thering gear 25 that works as the mass body of the rotary inertia massdamper 20, thereby enabling the inertia torque to be efficientlyobtained.

Further, in the damper device 10, 10X, the rotation speed of the ringgear 25 or the mass body is increased by the action of the planetarygear 21 so as to be higher than the rotation speed of the drive member11 (carrier). This reduces the weight of the ring gear 25 or the massbody while effectively ensuring the moment of inertia applied to thedriven member 15, 15X from the rotary inertia mass damper 20. This alsoenhances the flexibility in design of the rotary inertia mass damper 20and the entire damper device 10, 10X. The rotary inertia mass damper 20(planetary gear 21) may, however, be configured to decrease the rotationspeed of the ring gear 25 to be lower than the rotation speed of thedrive member 11, according to the magnitude of the moment of inertia ofthe ring gear 25 (mass body). Further, the planetary gear 21 may be adouble pinion-type planetary gear. Furthermore, the outer teeth gearportions 15 t of the driven member 15, 15 x, the gear tooth 23 t of thepinion gear 23 and the inner tooth 25 t of the ring gear 25 may be ahelical tooth with a helical tooth trace or a tooth with a straighttooth trace.

As described above, the configuration that two antiresonance points A1and A2 are set enables the antiresonance point A1 to be shifted towardthe lower frequency. Depending on the specification of the vehicle, themotor and so on equipped with the damper device 10, 10X, the multipleroot of Equation (5) (=½π·√{(k₁+k₂)/(2·J₂)} may be set to the aboveminimum frequency fa₁. Determining the spring constants k₁ and k₂ of thefirst and the second springs SP1 and SP2 and the moment of inertia J₂ ofthe intermediate member 12 based on the multiple root of Equation (5)also improves the vibration damping effect of the damper device 10, 10Xin the lower rotation speed range of the lockup area that is likely toincrease the vibration from the engine EG as shown by the broken linecurve in FIG. 5.

In the damper device 10, 10X described above, springs having theidentical specification (spring constant) are employed for the first andthe second springs SP1 and SP2. This is, however, not restrictive. Thespring constants k₁ and k₂ of the first and the second springs SP1 andSP2 may be different from each other (k₁>k₂ or k₁<k₂). This furtherincreases the value of the √ term (discriminant) in Equations (6) and(8) and further increases the interval between the two antiresonancepoints A1 and A2, thus further improving the vibration damping effect ofthe damper device in the low frequency range (low rotation speed range).In this case, the damper device 10, 10X may be provided with a stopperconfigured to restrict the deflection of one of the first and the secondsprings SP1 and SP2 (for example, one having the lower rigidity).

As described above, the ring gear 25 of the rotary inertia mass damper20 includes two side plates 251 respectively fixed to the gear body 250in such a manner that the inner circumferential surface of each sideplate 251 is located slightly inside tips of the inner teeth 25 t.However, each of the two side plates 251 may be fixed to the gear body250 in such a manner that the inner circumferential surface of each sideplate 251 is located radially inside bottoms of the inner teeth 25 t andradially outside the pinion shaft 24 supporting the pinion gear 23.Further, a diameter of the radially supporting portion 230 s of thepinion gear 23 (gear body 230) may also be reduced to be smaller thanthe above diameter. Namely, the inner circumferential surface of eachside plate 251 of the ring gear 25 may be made close to the pinion shaft24, so that the axial motion of the ring gear 25 is satisfactorilyrestricted by the pinion gears 23.

In order to restrict the axial motion of the ring gear 25 by the piniongears 23, the pinion gear 23 may be provided with a pair of supportingportions that have an annular shape for example and protrude radiallyoutside from both sides of the gear teeth 23 t and the side plates 251may be omitted from the ring gear 25. In such a configuration, thesupporting portions of the pinion gear 23 may be formed so as to opposeto at least the side face of the inner teeth 25 t of the ring gear 25 ora portion of the side face of the gear body 250.

As shown by two-dot chain lines in FIG. 1, the turbine runner 5 may becoupled with either the intermediate member 12 or the driven member 15.Further, the rotary inertia mass damper 20 may be configured to includethe turbine runner 5 as the mass body that rotates in accordance withrelative rotation between the drive member 11 and the driven member 15.In the damper device 10, 10X, the first and the second intermediateplate members 121 and 122 of the intermediate member 12 are arranged onboth sides of the first and the second input plate members 111 and 112in the axial direction and coupled with each other, but not limited tothis. That is, the first and the second intermediate plate members 121and 122 may be arranged on both sides of the driven member 15, 15Xbetween the first and the second input plate members 111 and 112 in theaxial direction and coupled with each other. Further, the intermediatemember 12 may be omitted from the damper device 10, 10X and a pluralityof springs that work in parallel to each other may be arranged betweenthe drive member 11 and the driven member 15, 15X.

FIG. 8 is a schematic configuration diagram illustrating a startingdevice 1Y including a damper device 10Y according to another embodimentof the disclosure, and FIG. 9 is a sectional view illustrating thestarting device 1Y. Among the components of the starting device 1Y andthe damper device 10Y, the same components to those of the startingdevice 1 and the damper device 10 described above are expressed by thesame reference signs and their repeated description is omitted.

The damper device 10Y shown in FIGS. 8 and 9 includes a lockup clutch 8Yconfigured as a single-disc hydraulic clutch. The lockup clutch 8Yincludes a lockup piston 80 that is disposed inside of the front cover 3so as to be close to an engine EG-side inner wall surface of the frontcover 3. The lockup piston 80 is fitted into the damper hub 7 to berotatable and movable in the axial direction. Friction members 88 areapplied on an outer circumferential-side and front cover 3-side surfaceof the lockup piston 80. A lockup chamber 89 is defined between thelockup piston 80 and the front cover 3. The lockup chamber 89 isconnected with a non-illustrated hydraulic control device via ahydraulic oil supply passage and an oil passage formed in the inputshaft IS. In the starting device 1Y, the non-illustrated hydrauliccontrol device sets the internal pressure of the fluid chamber 9 to behigher than the internal pressure of the lockup chamber 89 so as toengage the lockup clutch 8Y, thereby coupling the damper hub 7 with thefront cover via the damper device 10. On the other hand, thenon-illustrated hydraulic control device sets the internal pressure ofthe lockup chamber 89 to be higher than the internal pressure of thefluid chamber 9 so as to release the lockup clutch 8Y, therebydecoupling the damper hub 7 from the front cover 3. In the startingdevice 1Y, an inner circumferential portion of the turbine shell 50 isfixed to the turbine hub 52 by means of a plurality of rivets. Theturbine hub 52 is rotatably supported by the damper hub 7. The motion ofthe turbine hub 52 (turbine runner 5) in the axial direction of thestarting device 1Y is restricted by the damper hub 7 and a snap ringfitted to the damper hub 7.

The damper device 10Y of the staring device 1Y includes a drive member(input element) 11Y, a first intermediate member (first intermediateelement) 12Y, a second intermediate member (second intermediate element)14 and a driven member (output element) 15Y, as rotational elements. Thedamper device 10Y further includes a plurality of (for example, three inthis embodiment) first springs (first elastic bodies) SP1′ arranged totransmit the torque between the drive member 11Y and the firstintermediate member 12Y, a plurality of (for example, three in thisembodiment) second springs (second elastic bodies) SP2′ arranged totransmit the torque between the first intermediate member 12Y and thesecond intermediate member 14, and a plurality of (for example, nine inthis embodiment) inner springs (third elastic bodies) SPi′ arranged totransmit the torque between the second intermediate member 14 and thedriven member 15Y, as torque transmission elements (torque transmissionelastic bodies).

The plurality of first springs SP1′, the first intermediate member 12Y,the plurality of second springs SP2′, the second intermediate member 14and the plurality of inner springs SPi′ configure a torque transmissionpath TP between the drive member 11Y and the driven member 15Y. Thisconfiguration of the damper device 10Y is substantially equivalent tothe configuration that the plurality of inner springs SPi′ working inparallel are disposed between the driven member 15Y and the input shaftIS of the transmission TM in the damper device 10 shown in FIG. 1. Inthe damper device 10Y, the inner springs SPi′ are configured to have alarger spring constant (higher rigidity) than the spring constants(rigidities) of the first and the second springs SP1′ and SP2′.

The drive member 11Y of the damper device 10Y is configured in thebasically same structure as that of the drive member 11 of the damperdevice 10, 10X and works as the carrier of the planetary gear 21 of therotary inertia mass damper 20Y. As shown in FIG. 9, the drive member 11Yis coupled with the lockup piston 80 of the lockup clutch 8Y. That is, afirst input plate member 111Y of the drive member 11Y includes aplurality of engagement recesses 115 r that are formed at intervals inthe circumferential direction in the outer circumferential portion ofthe pinion gear supporting portions 115. A plurality of the engagementprotrusions 80 e are formed at intervals in the circumferentialdirection so as to extend from the lockup piston 80 in the axialdirection. Each of the engagement protrusions 80 e is fitted into anyone of the plurality of engagement recesses 115 r. Thus, the drivemember 11Y is capable of rotating integrally with the lockup piston 80.The front cover 3 is coupled with the drive member 11Y of the damperdevice 10Y by engagement of the lockup clutch 8. When the lockup clutch8Y is engaged, the plurality of engagement recesses 115 r of the piniongear supporting portions 115, which is a carrier, connects the pluralityof the engagement protrusions 80 e of the lockup piston 80 via a spline.When the lockup clutch 8Y is engaged, the lockup piston 80 is connectedto the front cover 3. That is, the pinion gear supporting portions 115are splined-engaged to the front cover 3 when the lockup clutch 8Y isengaged.

As shown in FIGS. 9 and 10, a plurality of (for example, nine in thisembodiment) spring supporting portions 111 s are formed at intervals (atequal intervals) in the circumferential direction in an innercircumferential portion of the first input plate member 111Y of thedrive member 111. Each of the spring supporting portions 111 s supports(guides) the corresponding inner spring SPi′ on the front cover 3-sidefrom the outer side in the radial direction. A plurality of (forexample, nine in this embodiment) spring supporting portions 112 s areformed at intervals (at equal intervals) in the circumferentialdirection in an inner circumferential portion of the second input platemember 112Y of the drive member 111. Each of the spring supportingportions 112 s supports (guides) the corresponding inner spring SPi′ onthe turbine runner 5-side from the outer side in the radial direction.The inner spring-accommodating windows 111 wi and 112 wi in the damperdevice 10 and so on are omitted from the first and the second inputplate member 111Y and 112Y.

On the side of the axial center of the damper device 10Y, the drivemember 11Y is coupled with the turbine coupling member 55Y that is fixedto the turbine hub 52 by means of a plurality of rivets together withthe turbine shell 50. As shown in FIG. 11, the second input plate member112Y includes a plurality of (for example, nine in this embodiment)engagement protrusions 112 e respectively protruding inwardly in theradial direction between the adjacent spring supporting portions 112 s.Each of the engagement protrusions 112 e is fitted into any one of theplurality of engagement recesses 55 r that are formed at intervals inthe circumferential direction in the outer circumferential portion ofthe turbine coupling member 55Y. Thus, the drive member 11Y and theturbine runner 5 are coupled with each other to be integrally rotated.

The first intermediate member 12Y of the damper device 10Y is configuredin the basically same structure as that of the intermediate member 12 ofthe damper device 10, 10X. The damping ratio ζ of the first intermediatemember 12Y is less than a value 1. On the other hand, the secondintermediate member 14 is configured in the basically same structure asthat of the driven member 15 of the damper device 10, 10X, but not fixedto the damper hub 7. The damping ratio ζ of the second intermediatemember 14 is less than a value 1.

The second intermediate member 14 is a plate-like annular member that isdisposed between the first and the second input plate members 111Y and112Y in the axial direction and is rotatably supported (aligned) by thedamper hub 7. A plurality of outer teeth gear portions 14 t are formedat intervals (at equal intervals) in the circumferential direction in anouter circumference surface (outer circumference portion) of the secondintermediate member 14 so as to be located radially outside the firstsprings SP1′, the second springs SP2′ and the inner springs SPi′. Thesecond intermediate member 14 works as the sun gear of the planetarygear 21. The outer teeth gear portion 14 t may be formed on the entireouter circumference portion of the second intermediate member 14.

As shown in FIGS. 9 and 10, the second intermediate member 14 isconfigured to include a plurality of (for example, three in thisembodiment) arc-shaped outer spring-accommodating windows 14 wo arrangedat intervals (at equal intervals) in the circumferential direction, aplurality of (for example, nine in this embodiment) arc-shaped innerspring-accommodating windows 14 wi arranged on an inner side in theradial direction of each outer spring-accommodating window 14 wo atintervals (at equal intervals) in the circumferential direction, aplurality of (for example, three in this embodiment) outer springcontact portions 14 co, and a plurality of (for example, nine in thisembodiment) inner spring contact portions loci. One outer spring contactportion 14 co is disposed between the outer spring-accommodating windows14 wo arranged adjacent to each other in the circumferential direction.The outer spring contact portion 14 co comes into contact with thecorresponding end of the second spring SP2′. One inner spring contactportion 14 ci is disposed between the inner spring-accommodating windows14 wi arranged adjacent to each other in the circumferential direction.The inner spring-accommodating windows 14 wi respectively have acircumferential length according to the natural length of the innerspring SPi′.

A plurality of (for example, three in this embodiment) stopper contactportions 14 st are formed at intervals in the circumferential directionso as to be capable of contacting with a portion of the drive member 11Yin accordance with the relative rotation between the drive member 11Yand the second intermediate member 14. Each of the stopper contactportions 14 st is extended in the axial direction from an outercircumferential portion of the second intermediate member 14 so as to belocated between the adjacent outer teeth gear portions 14 t in thecircumferential direction and contact with the root portion of theaxially extending portion 115 a (see FIG. 4). In the damper device 10Y,each of the stopper contact portions 14 st approaches the correspondingaxially extending portion 115 a of the first input plate member 111Y inaccordance with the relative rotation between the drive member 11Y andthe second intermediate member 14 and comes into contact with theportion of the first input plate member 111Y (the root portion of theaxially extending portion 115 a) when the input torque reaches thepredetermined torque T1 and the torsion angle of the drive member 11Yrelative to the second intermediate member 14 becomes equal to or largerthan the predetermined angle θref. Thus, the stopper contact portions 14st and the first input plate member 111Y configure a stopper 17Y thatrestricts the relative rotation between the drive member 11Y and thesecond intermediate member 14 and the deflections of the first and thesecond springs SP1′ and SP2′.

The driven member 15Y is configured to include two annular plates 150respectively fixed to the damper hub 7 by means of a plurality of rivetsso as to be spaced apart from each other in the axial direction of thedamper device 10Y and and opposed to each other. Each of the annularplates 150 includes a plurality of (for example, nine in thisembodiment) spring contact portions 15 c respectively protrudingoutwardly in the radial direction at intervals in the circumferentialdirection from an inner circumferential portion that is fixed to thedamper hub 7.

Each of the inner springs SPi′ is disposed in the corresponding innerspring-accommodating window 14 wi of the second intermediate member 14and disposed between the adjacent spring contact portions 15 c of thedriven member 15Y. In the mounting state of the damper device 10Y, eachof the inner spring contact portions 14 ci of the second intermediatemember 14 and each of the spring contact portions 15 c of the drivenmember 15Y are respectively disposed between the adjacent inner springsSPi′ in the circumferential direction and contact with ends of theadjacent inner springs SPi′. Each of the inner springs SPi′ is supported(guided) from the outer side in the radial direction by the springsupport portion 111 s of the first input plate member 111Y on the frontcover 3-side and the spring support portion 112 s of the second inputplate member 112 on the turbine runner 5-side.

As shown in FIGS. 9 and 10, each of the inner springs SPi′ is arrangedin the inner circumferential-side region in the fluid chamber 9 so as tobe surrounded by the first and the second springs SP1′ and SP2′. Thisconfiguration further shortens the axial length of both the damperdevice 10Y and the starting device 1 and reduces a centrifugal forceapplied to the inner springs SPi′ so as to decrease a frictional force(sliding resistance) generated when each of the inner springs SPi′ arepressed against the spring supporting portions 111 s and 112 s and thesecond intermediate member 14 by the centrifugal force.

An inner circumferential portion of the second intermediate member 14 isrotatably supported by the damper hub 7 between the two annular plates150 in the axial direction. As shown in FIG. 10, a plurality of secondstopper contact portions 14 z are formed at intervals (equal intervals)in the circumferential direction so as to respectively protrude inwardlyin the radial direction. Each of the second stopper contact portions 14z is loosely fitted into a corresponding one of a plurality of stopperrecesses 7 z that are formed at intervals in the circumferentialdirection in an outer circumference surface of the damper hub 7. Each ofthe stopper recesses 7 z has a circumferential length longer than thatof the each second stopper portion 14 z. Each of the second stoppercontact portions 14 z comes into contact with a corresponding one ofwall surfaces defining the stopper recess 7 z in accordance with therelative rotation between the second intermediate member 14 and thedriven member 15Y. That is, in the damper device 10Y, each of the secondstopper contact portions 14 z approaches the corresponding one of wallsurfaces defining the stopper recess 7 z in accordance with relativerotation between the second intermediate member 14 and the driven member15Y (damper hub 7) and comes into contact with the corresponding one ofwall surfaces defining the stopper recess 7 z when the input torque or atorque applied from an axle side to the driven member 15Y (driventorque) reaches the above torque T2 corresponding to the maximum torsionangle θ max. Thus, the second stopper contact portions 14 z and thestopper recesses 7 z configure a second stopper 18 that restricts therelative rotation between the second intermediate member 14 and thedriven member 15Y and the deflections of the inner springs SPi′.

When the lockup by the lockup clutch 8Y is released in the startingdevice 1Y with the above described damper device 10Y, as seen from FIG.8, the torque (power) transmitted from the engine EG to the front cover3 is transmitted to the input shaft IS of the transmission TM via a pathincluding the pump impeller 4, the turbine runner 5, the drive member11Y, the first springs SP1′, the first intermediate member 12Y, thesecond springs SP2′, the second intermediate member 14, the innersprings SPi′, the driven member 15Y and the damper hub 7. On the otherhand, when the lockup is executed by the lockup clutch 8Y of thestarting device 1Y, on the other hand, the torque transmitted from theengine EG to the drive member 11 via the front cover 3 and the lockupclutch 8 is transmitted to the driven member 15 and the damper hub 7 viathe torque transmission path TP including the plurality of first springsSP1′, the first intermediate member 12Y, the plurality of second springsSP2′, the second intermediate member 14 and the plurality of innersprings SPi′, and the rotary inertia mass damper 20Y. At this time, therotary inertia mass damper 20Y connected with the drive member 11 andthe second intermediate member 14 mainly transmits the inertia torque tothe driven member 15Y via the second intermediate member 14 and theinner springs SPi′.

When the input torque into the drive member 11 becomes equal to orhigher than the above torque T1, the stopper 17Y restricts the relativerotation between the drive member 11Y and the second intermediate member14 and the deflections of the first and the second springs SP1′ andSP2′. Thus, until the input torque transmitted to the drive member 11reaches the above torque T2, the torque (power) transmitted to the drivemember 11Y is transmitted to the input shaft IS of the transmission TMvia a path including the drive member 11Y, the first springs SP1′, thefirst intermediate member 12Y, the second springs SP2′, the secondintermediate member 14, and components of the rotary inertia mass damper20Y, that rotate integrally, the plurality of inner springs SPi′, thedriven member 15Y and the damper hub 7. Accordingly, the damper device10Y has two-step (two-stage) damping characteristics. When the inputtorque into the drive member 11 becomes equal to or higher than theabove torque T2, the second stopper 18 restricts the relative rotationbetween the second intermediate member 14 and the driven member 15Y andthe deflections of the inner springs SPi. Thus, all of the elements fromdrive member 11 to the damper hub 7 rotate integrally.

Further, in the damper device 10Y, the rotary inertia mass damper 20Y isprovided in parallel to the first and the second springs SP1′ and SP2′and the first intermediate member 12Y. Accordingly, in the damper device10Y, two (multiple) natural frequencies may be set for the torquetransmission path from the drive member 11Y to the second intermediatemember 14 in the state that the deflections of at least the first andthe second springs SP1′ and SP2′ are allowed, and a resonance of thefirst intermediate member 12Y (second resonance) may occur at the higherrotation speed (the higher frequency) than a first resonance. Thisenables a total of two antiresonance points that provide theoreticallyzero vibration amplitude of the driven member 15Y to be set in thedamper device 10Y.

The damper device 10Y is especially suitable to be used in combinationwith a transmission TM for rear-wheel drive. In the transmission TM forrear-wheel drive having a long length from one end of an input shaft IS(starting device 1Y-side end) to one end of a non-illustrated outputshaft (wheel side-end), the rigidities of the input shaft IS coupledwith the driven member 15Y of the damper device 10Y and of the outputshaft (and additionally an intermediate shaft) are decreased.Accordingly a natural frequency (resonance frequency) determined by themoments of inertia of these shaft members is decreased (lowered) by theeffect of the moment of inertia of the entire rotary inertia mass damper20Y. This may obviously cause a resonance, which is supposed to occur atthe high rotation speed of the drive member 11Y (engine EG), even in alow rotation speed range. The configuration that the rotary inertia massdamper 20Y is connected with the drive member 11Y and the secondintermediate member 14 of the damper device 10Y, on the other hand,causes the inner springs SPi′ to be placed between the rotary inertiamass damper 20Y and the input shaft IS of the transmission TM connectedwith the driven member 15Y, thereby substantially separating the rotaryinertia mass damper 20Y from the input shaft IS. This configurationenables two antiresonance points to be set and remarkably effectivelyreduces the effect of the moment of inertia of the entire rotary inertiamass damper 20Y on a natural frequency determined by the moment ofinertia of the shaft member connected with the driven member 15Y and soon.

The damper device 10Y may, however, be used in combination with atransmission TM for front-wheel device. In the case where the damperdevice 10Y is combined with the transmission TM for front-wheel vehicle,the configuration of the damper device 10Y also remarkably effectivelyreduces the effect of the moment of inertia of the entire rotary inertiamass damper 20Y on the natural frequency determined by the moment ofinertia of the shaft member coupled with the driven member 15Y and soon, and additionally improves the vibration damping performance of thedamper device 10Y by a further decrease of the rigidity. The damperdevice 10Y may be configured such as to include any additionalintermediate member and springs (elastic bodies) between the firstintermediate member 12Y and the second intermediate member 14.Furthermore, the turbine runner 5 may be coupled with one of the firstand the second intermediate members 12Y and 14 as shown by a two-dotchain line in FIG. 8 or may be coupled with the driven member 15Y.

Further, the rotary inertia mass damper 20Y may be configured to includethe turbine runner 5 as the mass body that rotates in accordance withrelative rotation between the drive member 11Y and the secondintermediate member 14 (driven member 15Y). The stopper contact portions14 st may be extended in the axial direction from the outercircumferential portion of the second intermediate member 14 so as to becapable of contacting with the second input plate member 112 (forexample, axially extending portion 116 a). The plurality of stoppercontact portions 14 st may be respectively extended in the radialdirection from the outer circumferential portion of the secondintermediate member 14 so as to be capable of respectively contactingwith a rivet (coupling member) that couples the first input plate member111Y with the second input plate member 112Y. As shown by two-dot chainlines in FIG. 8, the second stopper 18 may restrict the relativerotation between the drive member 11Y and the driven member 15Y. In thedamper device 10Y, the first and the second intermediate plate members121 and 122 of the intermediate member 12Y are arranged on both sides ofthe first and the second input plate members 111Y and 112Y in the axialdirection and coupled with each other, but not limited to this. That is,the first and the second intermediate plate members 121 and 122 of theintermediate member 12Y may be arranged on both sides of the secondintermediate member 14 between the first and the second input platemembers 111Y and 112Y in the axial direction and coupled with eachother. Further, the intermediate member 12Y may be omitted from thedamper device 10Y and a plurality of springs that work in parallel toeach other may be arranged between the drive member 11Y and the secondintermediate member 14.

FIG. 12 is a sectional view illustrating a starting device 1Z includinga damper device 10Z according to another embodiment of the disclosure.Among the components of the starting device 1Z and the damper device10Z, the same components to those of the starting device 1, 1Y and so onand the damper device 10, 10Y and so on described above are expressed bythe same reference signs and their repeated description is omitted.

The damper device 10Z of the staring device 1Z shown in FIG. 12 includesa drive member 11Z to which the torque from the engine EG istransmitted, a driven member 15Z, a plurality of outer springs SPo and aplurality of inner springs SPi respectively arranged to transmit thetorque between the drive member 11Z and the driven member 15Z, and arotary inertia mass damper 20Z with the ring gear 25 or the mass bodythat rotates in accordance with a relative rotation between the drivemember 11Z and the driven member 15Z. In the damper device 10Z, theinner springs SPi are arranged to work in parallel to the outer springsSPo after the input torque into the drive member 11Z reaches thepredetermined torque (first threshold value) T1 and the torsion angle ofthe drive member 11Z relative to the driven member 15Z becomes equal toor larger than the predetermined angle. The damper device 10 accordinglyhas two-step (two-stage) damping characteristics.

The drive member 11Z includes an annular first and second input platemembers (first and second rotational support members) 1112 and 112Z thatare coupled with each other by means of a plurality of rivets 117 so asto be opposed to each other in the axial direction of the damper device10Z and rotatably support the plurality of the pinion gears 23 of theplanetary gear 21. The first input plate member 1112 is configured toinclude a plurality of outer spring contact portions 111 co thatrespectively contact with a corresponding end of the outer spring SPoand a plurality of inner spring contact portions 111 ci thatrespectively contact with a corresponding end of the inner spring SPi.The first input plate member 1112 includes a plurality of engagementrecesses 115 r that are formed at intervals in the circumferentialdirection in the outer circumferential portion of the pinion gearsupporting portions 115. The plurality of the engagement protrusions 80e are formed at intervals in the circumferential direction so as toextend from the lockup piston 80 in the axial direction. Each of theengagement protrusions 80 e is fitted into any one of the plurality ofengagement recesses 115 r. The second input plate member 112Z isconfigured to include a plurality of outer spring contact portions 112co that respectively contact with the corresponding end of the outerspring SPo and a plurality of inner spring contact portions 112 ci thatrespectively contact with the corresponding end of the inner spring SPiand is rotatably supported by the damper hub 7.

The driven member 15Z is fixed to the damper hub 7 by means of aplurality of rivets and disposed between the first and the second inputplate members 1112 and 112Z in the axial direction. As shown in FIG. 12,the driven member 15Z is configured to include a plurality of outerspring contact portions 15 co that respectively contact with thecorresponding end of the outer spring SPo and a plurality of innerspring contact portions 15 ci that respectively contact with thecorresponding end of the inner spring SPi. Further, the driven member15Z includes a plurality of outer teeth gear portions 15 t formed atintervals in the circumferential direction in the outer circumferentialportion thereof so as to respectively mesh with the corresponding piniongear 23 of the rotary inertia mass damper 20Z and works as the sun gearof the rotary inertia mass damper 20Z.

The damper device 10Z further includes a stopper 17Z configured torestrict a relative rotation between the drive member 11Z and the drivenmember 15Z. In the embodiment of FIG. 12, the stopper 17Z includes aplurality of stopper contact portions 15 st formed in the outercircumferential portion of the driven member 15Z so as to be locatedbetween the adjacent outer teeth gear portions 15 t in thecircumferential direction. Each of the stopper contact portions 15 stcomes into contact with a collar 118 fitted to the rivet 117 thatcouples the first input plate member 1112 with the second input platemember 112Z in accordance with the relative rotation between the drivemember 11Z and the driven member 15Z.

Thus, in the damper device 10Z, the relative rotation between the drivemember 11Z and the driven member 15Z is restricted so as to prevent theexcessive load including the inertia torque from the rotary inertia massdamper 20Z from acting on the outer and the inner springs SPo and SPiwhen the larger torque is transmitted between the drive member 11Z andthe driven member 15Z, thereby satisfactorily protecting the outer andthe inner springs SPo and SPi. Further, the stopper contact portions 15st are arranged in the outer circumferential portion of the drivenmember 15Z (sun gear) so as to make a distance from the axial center ofthe damper device 10Z to the stopper contact portion 15 st closer to adistance from the axial center of the damper device 10Z to the piniongear supporting portions 115 and 116 in the drive member 11Z. Thisdecreases moment acting on the drive member 11Z (first and second inputplate members 1112 and 112Z) that supports the plurality of pinion gears23 and prevents deformation and so on of the drive member 11Z when thestopper contact portions 15 st contacts with the drive member 11Z so asto restrict the relative rotation between the drive member 11Z and thedriven member 15Z. Accordingly, the durability of the damper device 10Zwith the rotary inertia mass damper 20Z can be improved.

FIG. 13 is a schematic configuration diagram illustrating a startingdevice 1V including a damper device 10V according to another embodimentof the disclosure. Among the components of the starting device 1V andthe damper device 10V, the same components to those of the startingdevice 1, 1Y and so on and the damper device 10, 10Y and so on describedabove are expressed by the same reference signs and their repeateddescription is omitted.

The damper device 10V of the staring device 1V shown in FIG. 13 includesa drive member 11V to which the torque from the engine EG istransmitted, an intermediate member 12V, a driven member 15V, aplurality of first springs SP1 v arranged to transmit the toque betweenthe drive member 11V and the intermediate member 12V, a plurality ofsecond springs SP2 v arranged to transmit the torque between theintermediate member 12V and the driven member 15V, and a rotary inertiamass damper 20V with the ring gear 25 or the mass body that rotates inaccordance with a relative rotation between the drive member 11V and theintermediate member 12V.

The drive member 11V includes an annular first and second input platemembers (first and second rotational support members) 111V and 112V thatare coupled with each other by means of the plurality of rivets 117 soas to be opposed to each other in the axial direction of the damperdevice 10V and rotatably support the plurality of the pinion gears 23 ofthe planetary gear 21. The first input plate member 111V is configuredto include a plurality of spring contact portions 111 c thatrespectively contact with a corresponding end of the first spring SP1 vand a plurality of engagement recesses 115 r into which thecorresponding engagement protrusion 80 e of the lockup piston 80 isfitted. The second input plate member 112V is configured to include aplurality of spring contact portions 112 c that respectively contactwith the corresponding end of the first spring SP1 v.

The intermediate member 12V is disposed between the first and the secondinput plate members 111V and 112V in the axial direction. As shown inFIG. 13, the intermediate member 12V is configured to include aplurality of outer spring contact portions 12 co that respectivelycontact with the corresponding end of the first spring SP1 v and aplurality of inner spring contact portions 12 ci that respectivelycontact with the corresponding end of the second spring SP2 v. Further,the intermediate member 12V includes a plurality of outer teeth gearportions 12 t arranged at intervals in the circumferential direction inthe outer circumferential portion thereof so as to respectively meshwith the corresponding pinion gear 23 of the rotary inertia mass damper20V and works as the sun gear of the rotary inertia mass damper 20V. Thedriven member 15V includes the first and the second driven plate members151 and 152 arranged on both sides of the intermediate member 12V in theaxial direction and fixed to the damper hub 7. The first and the seconddriven member 151 and 152 respectively include a plurality of springcontact portions (not shown) that respectively contact with thecorresponding end of the second spring SP2 v.

The damper device 10V further includes a stopper 17V configured torestrict a relative rotation between the drive member 11V and theintermediate member 12V. In the embodiment of FIG. 13, the stopper 17Vincludes a plurality of stopper contact portions 12 st formed in theouter circumferential portion of the intermediate member 12V so as to belocated between the adjacent outer teeth gear portions 12 t in thecircumferential direction. Each of the stopper contact portions 12 stcomes into contact with the collar 118 fitted to the rivet 117 thatcouples the first input plate member 111V with the second input platemember 112V in accordance with the relative rotation between the drivemember 11V and the intermediate member 12V.

Thus, in the damper device 10V, the relative rotation between the drivemember 11V and the intermediate member 12V is restricted so as toprevent the excessive load including the inertia torque from the rotaryinertia mass damper 20V from acting on the outer and the first springsSP1 v when the larger torque is transmitted between the drive member 11Vand the intermediate member 12V, thereby satisfactorily protecting thefirst springs SP1 v. Further, the stopper contact portions 12 st arearranged in the outer circumferential portion of the intermediate member12V (sun gear) so as to make a distance from the axial center of thedamper device 10V to the stopper contact portion 12 st closer to adistance from the axial center of the damper device 10V to the piniongear supporting portions 115 and 116 in the drive member 11V. Thisdecreases moment acting on the drive member 11V (first and second inputplate members 111V and 112V) that supports the plurality of pinion gears23 and prevents deformation and so on of the drive member 11V when thestopper contact portions 12 st contacts with the drive member 11V so asto restrict the relative rotation between the drive member 11V and theintermediate member 12V. Accordingly, the durability of the damperdevice 10V with the rotary inertia mass damper 20V can be improved.

As has been described above, a damper device (10, 10X, 10Y) according toone aspect of the disclosure is configured to include a first, a second,and a third rotational element (11, 11Y, 12, 12Y, 15, 15X, 14), a firstelastic body (SP1, SP1′) arranged to transmit a torque between the firstelement and the second element (11, 11Y, 12, 12Y), a second elastic body(SP2, SP2′) arranged to transmit a torque between the second element andthe third element (12, 12Y, 15, 15X, 14), and a rotary inertia massdamper (20, 20Y) with a mass body (25) rotating in accordance withrelative rotation between the first rotational element and the thirdrotational element (11, 11Y, 15, 15X, 14). The damper device includes astopper (17, 17Y) configured to restrict the relative rotation betweenthe first rotational element and the third rotational element (11, 11Y,15, 15X, 14). The rotary inertia mass damper (20, 20Y) is configured toinclude a planetary gear (21) that includes a sun gear (15, 15X, 15 t,14, 14 t), a plurality of pinion gears (23) that mesh with the sun gear(15, 15X, 15 t, 14, 14 t), and a ring gear (25) that works as the massbody. The first rotational element (11, 11Y) is configured to include afirst rotational support member and a second rotational support member(111, 112, 111Y, 112Y) that are coupled with each other so as to beopposed to each other in an axial direction of the damper device (10,10X, 10Y). The first and the second rotational support members (111,112, 111Y, 112Y) rotatably support the plurality of pinion gears (23).The third rotational element (15, 15X, 14) is configured to include anouter teeth gear portion (15 t, 14 t) that meshes with the plurality ofpinion gears (23) in an outer circumferential portion thereof. The thirdrotational element (15, 15X, 14) is disposed between the first and thesecond rotational support members (111, 112, 111Y, 112Y) in the axialdirection so as to work as the sun gear. The stopper (17, 17Y) isconfigured to include a contact portion (15 st, 14 st) arranged in theouter circumferential portion of the third rotational element (15, 15X,14) so as to contact with a portion of the first rotational element (11,11Y) in accordance with the relative rotation between the firstrotational element and the third rotational element (11, 11Y, 15, 15X,14).

The first rotational element of the damper device includes the first andthe second rotational support member that are coupled with each other soas to be opposed to each other in the axial direction of the damperdevice and rotatably support the plurality of pinion gears. The thirdrotational element includes the outer teeth gear portion that mesheswith the plurality of pinion gears in the outer circumferential portionthereof and is disposed between the first and the second rotationalsupport members in the axial direction so as to work as the sun gear.The damper device includes the stopper configured to restrict therelative rotation between the first rotational element and the thirdrotational element. The stopper includes the contact portion arranged inthe outer circumferential portion of the third rotational element so asto contact with the portion of the first rotational element inaccordance with the relative rotation between the first rotationalelement and the third rotational element.

Thus, the relative rotation between the first rotational element and thethird rotational element is restricted so as to prevent an excessiveload including the inertia torque from the rotary inertia mass damperfrom acting on the first and the second springs when a larger torque istransmitted between the first and the third rotational elements, therebysatisfactorily protecting the first and the second springs. Further, thecontact portion of the stopper is arranged in the outer circumferentialportion of the third rotational element (sun gear) so as to make adistance from the axial center of the damper device to the contactportion closer to a distance from the axial center of the damper deviceto a support portion of the pinion gears in the first rotationalelement. This decreases moment acting on the first rotational element(the first and the second rotational support members) that supports theplurality of pinion gears and prevents deformation and so on of thefirst rotational element when the contact portion contacts with thefirst rotational element so as to restrict the relative rotation betweenthe first rotational element and the third rotational element.Accordingly, the durability of the damper device with the rotary inertiamass damper can be improved.

The third rotational element (15, 15 x, 14) may be configured to includea plurality of outer teeth gear portions (15 t, 14 t). The plurality ofouter teeth gear portions (15 t, 14 t) may be arranged at intervals in acircumferential direction in the outer circumferential portion. Aplurality of contact portions (15 st, 14 st) may be arranged in theouter circumferential portion so as to be located between the adjacentouter teeth gear portions (15 t, 14 t) in the circumferential direction.That is, in the sun gear of the planetary gear included in the rotaryinertia mass damper, the outer teeth gear portions may be formed in arange corresponding to a moving range of each pinion gear and is notnecessarily required to be formed in the entire outer circumferentialportion of the sun gear (the third rotational element). Accordingly,when the plurality of outer teeth gear portions are arranged atintervals in the circumferential direction in the outer circumferentialportion of the third rotational element, the contact portion of thestopper may be located between the adjacent outer teeth gear portions inthe circumferential direction so as to suppress overall size expansionand complication of a structure of the first element, the thirdrotational element and the damper device even if the contact portion(the stopper) is arranged in the third rotational element.

The contact portion (15 st, 14 st) may be configured to extend in theaxial direction from the outer circumferential portion of the thirdrotational element (15, 15X, 14) so as to be capable of contacting withone of the first and the second rotational support members (111, 112).This satisfactorily suppresses overall size expansion and complicationof the structure of the first element, the third rotational element andthe damper device even if the contact portion (the stopper) is arrangedin the third rotational element.

The contact portion (15 st) may be configured to extend in a radialdirection of the damper device (10 x) from the outer circumferentialportion of the third rotational element (15X) so as to be capable ofcontacting with a coupling member (113) by which the first and thesecond rotational support members (111, 112) are coupled. This enablesthe third rotational element to be formed flat, thereby reducingmachining costs of the third rotational element.

The damper device (10, 10X) may further include an input element (11),an intermediate element (12), and an output element (15, 15X). The firstrotational element may be the input element (11), the second rotationalelement may be the intermediate element (12), and the third element maybe the output element (15, 15X). This enables two antiresonance points,where the vibration transmitted from the input element to the outputelement via the first and the second springs and the vibrationtransmitted from the input element to the output element via the rotaryinertia mass damper are theoretically cancelled out each other, to beset in the damper device. Thus, the damper device of this aspectremarkably effectively improves the vibration damping performance of thedamper device by making the frequencies of the two antiresonance pointsequal to (closer to) the frequency of the vibrations (resonances) to bedamped by the damper device.

The damper device (10, 10X) may further include a third elastic body(SPi) arranged to work in parallel to the first and the second elasticbodies (SP1, SP2) and to transmit a torque between the input element(11) and the output element (15, 15X). This enables the damper device tohave two-step (two-stage) damping characteristics.

The damper device (10Y) may further include an input element (11Y), afirst intermediate element (12Y), a second intermediate element (14), anoutput element (15), and a third elastic body (SPi′) arranged totransmit a torque between the second intermediate element (14) and theoutput element (15). The first rotational element may be the inputelement (11Y), the second rotational element may be the firstintermediate element (12Y), and the third element may be the secondintermediate element (14). In the damper device, two antiresonancepoints can be set so as to remarkably effectively improve the vibrationdamping performance of the damper device by making the frequencies ofthe two antiresonance points equal to (closer to) the frequency of thevibrations (resonances) to be damped by the damper device. Further, inthe damper device of this aspect, the rotary inertia mass damper isconnected with the input element and the second intermediate element ofthe damper device. This causes the third elastic body to be placedbetween the rotary inertia mass damper and a member coupled with theoutput element, thereby substantially separating the rotary inertia massdamper from the member. This enables two antiresonance points to be setand remarkably effectively reduces the effect of the moment of inertiaof the entire rotary inertia mass damper on a natural frequencydetermined by the moment of inertia of the member coupled with theoutput element. Even when the member coupled with the output element ofthe damper device has a low rigidity and the natural frequency(resonance frequency) determined by the moment of inertia of the memberis decreased by the effect of the moment of inertia of the entire rotaryinertia mass damper, this results in effectively suppressing a resonancewhich is supposed to occur at the high rotation speed of the inputelement from being obviously caused even in a low rotation range.

The damper device (10, 10X, 10Y) may be configured not to restrictdeflections of the first and the second elastic bodies (SP1, SP2) untilan input torque transmitted to the input element (11, 11Y) becomes equalto or larger than a predetermined threshold value (T2, T1).

The torque from the engine (EG) may be transmitted to the input element(11, 11Y) via a clutch (8, 8Y), and the output element (15, 15X, 15Y)may be connected with an input shaft (IS) of a transmission (TM).

A damper device (10Z) according to another aspect of the disclosure isconfigured to include an input element (11Z) to which a torque from anengine (EG) is transmitted, an output element (15Z), an elastic body(SPo, SPi) arranged to transmit a torque between the input element (11Z)and the output element (15Z), and a rotary inertia mass damper (20Z)with a mass body (25) rotating in accordance with relative rotationbetween the input element (11Z) and the output element (15Z). The damperdevice (10Z) includes a stopper (17Z) configured to restrict therelative rotation between the input element (11Z) and the output element(15Z). The rotary inertia mass damper (20Z) is configured to include aplanetary gear (21) that includes a sun gear (15Z, 15 t), a plurality ofpinion gears (23) that mesh with the sun gear (15Z, 15 t), and a ringgear (25) that works as the mass body. The input element (11Z) isconfigured to include a first rotational support member and a secondrotational support member (111Z, 112Z) that are coupled with each otherso as to be opposed to each other in an axial direction of the damperdevice (10Z). The first and the second rotational support members (111Z,112Z) rotatably support the plurality of pinion gears (23). The outputelement (15Z) is configured to include a plurality of outer teeth gearportions (15 t) arranged at intervals in a circumferential direction inthe outer circumferential portion thereof so as to mesh with any of theplurality of pinion gears (23). The output element (15Z) is disposedbetween the first and the second rotational support members (111Z, 112Z)in the axial direction so as to work as the sun gear. The stopper (17Z)is configured to include a contact portion (15 st) arranged in the outercircumferential portion of the output element (15Z) so as to be locatedbetween the adjacent outer teeth gear portions (15 t) in thecircumferential direction and to contact with a portion (118) of theinput element (11Z) in accordance with the relative rotation between theinput element (11Z) and the output element (15Z).

The damper device is capable of restricting the relative rotationbetween the input element and the output element so as to prevent anexcessive load including the inertia torque from the rotary inertia massdamper from acting on the elastic body when a larger torque istransmitted between the input element and the output element, therebysatisfactorily protecting the elastic body. Further, the contact portionof the stopper is arranged in the outer circumferential portion of theoutput element (sun gear) so as to make a distance from the axial centerof the damper device to the contact portion closer to a distance fromthe axial center of the damper device to a support portion of the piniongears in the input element. This decreases moment acting on the inputelement (the first and the second rotational support members) thatsupports the plurality of pinion gears and prevents deformation and soon of the input element when the contact portion contacts with the inputelement so as to restrict the relative rotation between the inputelement and the output element. Accordingly, the durability of thedamper device with the rotary inertia mass damper can be improved.

A damper device (10V) according to yet another aspect of the disclosureis configured to include an input element (11V) to which a torque froman engine (EG) is transmitted, an intermediate element (12V), an outputelement (15V), a first elastic body (SP1 v) arranged to transmit atorque between the input element (11V) and the intermediate element(12V), a second elastic body (SP2 v) arranged to transmit a torquebetween the intermediate element (12V) and the output element (15V), anda rotary inertia mass damper (20V) with a mass body (25) rotating inaccordance with relative rotation between the input element (11V) andthe intermediate element (12V). The damper device (10V) includes astopper (17V) configured to restrict the relative rotation between theinput element (11V) and the intermediate element (12V). The rotaryinertia mass damper (20V) is configured to include a planetary gear (21)that includes a sun gear (12V, 12 t), a plurality of pinion gears (23)that mesh with the sun gear (12V, 12 t), and a ring gear (25) that worksas the mass body. The input element (11V) is configured to include afirst rotational support member and a second rotational support member(111V, 112V) that are coupled with each other so as to be opposed toeach other in an axial direction of the damper device (10V). The firstand the second rotational support members (111V, 112V) rotatably supportthe plurality of pinion gears (23). The intermediate element (12V) isconfigured to include a plurality of outer teeth gear portions (12 t)arranged at intervals in a circumferential direction in the outercircumferential portion thereof so as to mesh with any of the pluralityof pinion gears (23). The intermediate element (12V) is disposed betweenthe first and the second rotational support members (111V, 112V) in theaxial direction so as to work as the sun gear. The stopper (17V) isconfigured to include a contact portion (12 st) arranged in the outercircumferential portion of the intermediate element (12V) so as to belocated between the adjacent outer teeth gear portions (12 t) in thecircumferential direction and to contact with a portion (118) of theinput element (11V) in accordance with the relative rotation between theinput element (11V) and the intermediate element (12V).

The damper device is capable of restricting the relative rotationbetween the input element and the intermediate element so as to preventan excessive load including the inertia torque from the rotary inertiamass damper from acting on the first elastic body when a larger torqueis transmitted between the input element and the intermediate element,thereby satisfactorily protecting the first elastic body. Further, thecontact portion of the stopper is arranged in the outer circumferentialportion of the intermediate element (sun gear) so as to make a distancefrom the axial center of the damper device to the contact portion closerto a distance from the axial center of the damper device to a supportportion of the pinion gears in the input element. This decreases momentacting on the input element (the first and the second rotational supportmembers) that supports the plurality of pinion gears and preventsdeformation and so on of the input element when the contact portioncontacts with the input element so as to restrict the relative rotationbetween the input element and the intermediate element. Accordingly, thedurability of the damper device with the rotary inertia mass damper canbe improved.

The disclosure is not limited to the above embodiments in any sense butmay be changed, altered or modified in various ways within the scope ofextension of the disclosure. Additionally, the embodiments describedabove are only concrete examples of some aspect of the disclosuredescribed in Summary and are not intended to limit the elements of thedisclosure described in Summary.

INDUSTRIAL APPLICABILITY

The techniques according to the disclosure is applicable to, forexample, the field of manufacture of the damper device.

The invention claimed is:
 1. A damper device comprising: a plurality ofrotational elements including an input element to which a torque from anengine is transmitted and an output element, a plurality of elasticbodies respectively arranged to transmit a torque between the inputelement and the output element, a rotary inertia mass damper with a massbody that oscillates in accordance with relative rotation between afirst rotational element which is one of the plurality of rotationalelements and a second rotational element different from the firstrotational element, and a housing that houses the plurality ofrotational elements, the plurality of elastic bodies and the rotaryinertia mass damper, the housing including a front cover, wherein therotary inertia mass damper is configured to include a planetary gearthat includes a sun gear, a plurality of pinion gears, a carrier thatrotatably supports the plurality of pinion gears, and a ring gear thatmeshes with the plurality of pinion gears, wherein the carrier isarranged to rotate integrally with the first element, wherein the sungear is arranged to rotate integrally with the second element, whereinthe ring gear works as the mass body of the rotary inertia mass damper,wherein the carrier is centered by either the sun gear or a member thatrotates integrally with the sun gear by being radially supported byeither the sun gear or the member that rotates integrally with the sungear, and wherein the carrier is spline-engaged to the front cover whena lockup clutch is engaged.
 2. The damper device according to claim 1,wherein the first rotational element is the input element and the secondrotational element is the output element.
 3. The damper device accordingto claim 1, wherein the ring gear is not aligned by the plurality ofrotational elements including the input element and the output element.4. The damper device according to claim 1, wherein the first rotationalelement is configured to include two plate members arranged to beopposed to each other in an axial direction such as to support theplurality of elastic bodies and to rotatably support the plurality ofpinion gears, the two plate members working as the carrier, and whereinat least one of the two plate members is aligned by either the sun gearor the member that rotates integrally with the sun gear.
 5. The damperdevice according to claim 4, wherein the output element is a singleoutput plate member disposed between the two plate members in the axialdirection, the output plate member including outer teeth in an outercircumference thereof such as to work as the sun gear.
 6. The damperdevice according to claim 4, wherein the carrier is aligned by an outputmember of the damper device that rotates integrally with the sun gearand is connected with an input shaft of a transmission.
 7. The damperdevice according to claim 1, wherein the plurality of rotationalelements includes an intermediate element, and wherein the plurality ofelastic bodies include a first elastic body arranged to transmit atorque between the input element and the intermediate element, and asecond elastic body arranged to transmit a torque between theintermediate element and the output element.